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  1. Genetic counseling/consultation in South-East Asia: a report from the workshop at the 10th Asia pacific conference on human genetics
    Zayts O, Sarangi S, Thong MK, Chung BH, Lo IF, Kan AS, et al.
    J Genet Couns, 2013 Dec;22(6):917-24.
    PMID: 24048708 DOI: 10.1007/s10897-013-9646-7
    This paper reports on the workshop 'Genetic Counseling/Consultations in South-East Asia' at the 10(th) Asia Pacific Conference on Human Genetics in Kuala Lumpur, Malaysia, in December 2012. The workshop brought together professionals and language/communication scholars from South-East Asia, and the UK. The workshop aimed at addressing culture- and context-specific genetic counseling/consultation practices in South-East Asia. As a way of contextualizing genetic counseling/consultation in South-East Asia, we first offer an overview of communication-oriented research generally, drawing attention to consultation and counseling as part of a communicative continuum with distinctive interactional features. We then provide examples of genetic counseling/consultation research in Hong Kong. As other countries in South-East Asia have not yet embarked on communication-oriented empirical research, we report on the current practices of genetic counseling/consultation in these countries in order to identify similarities and differences as well as key obstacles that could be addressed through future research. Three issues emerged as 'problematic': language, religion and culture. We suggest that communication-oriented research can provide a starting point for evidence-based reflections on how to incorporate a counseling mentality in genetic consultation. To conclude, we discuss the need for creating a platform for targeted training of genetic counselors based on communication-oriented research findings.
    Matched MeSH terms: Genetic Counseling*
  2. Fulltext Thalassaemia Care in Terengganu – A Local Report
    Nazzlin Dizana Din
    Malaysian Journal of Paediatrics and Child Health, 2020;26(2):1-5.
    MyJurnal
    Inherited thalassaemia disease is commonly found in many countries of the world. Care of the disease requires comprehensive management strategies comprising of clinical management of both transfusion dependant thalassaemia (TDT) and non-transfusion dependant thalassaemia (NTDT). It also includes preventive measures such as screening programmes and genetic counseling in order to contain the genetic transmission. At the moment, the only cure is through haematopoeitic stem cell transplant (HSCT). This report illustrates thalassaemia disease prevalence in the Terengganu state and the evolution of care since National Thalassaemia Programme was launched in 2009.
    Matched MeSH terms: Genetic Counseling
  3. Genetic counseling services and development of training programs in Malaysia
    Lee JM, Thong MK
    J Genet Couns, 2013 Dec;22(6):911-6.
    PMID: 23615969 DOI: 10.1007/s10897-013-9589-z
    Genetic counseling service is urgently required in developing countries. In Malaysia, the first medical genetic service was introduced in 1994 at one of the main teaching hospitals in Kuala Lumpur. Two decades later, the medical genetic services have improved with the availability of genetic counseling, genetic testing and diagnosis, for both paediatric conditions and adult-onset inherited conditions, at four main centers of medical genetic services in Malaysia. Prenatal diagnosis services and assisted reproductive technologies are available at tertiary centres and private medical facilities. Positive developments include governmental recognition of Clinical Genetics as a subspecialty, increased funding for genetics services, development of medical ethics guidelines, and establishment of support groups. However, the country lacked qualified genetic counselors. Proposals were presented to policy-makers to develop genetic counseling courses. Challenges encountered included limited resources and public awareness, ethical dilemmas such as religious and social issues and inadequate genetic health professionals especially genetic counselors.
    Matched MeSH terms: Genetic Counseling*
  4. Fulltext Medical genetics in developing countries in the Asia-Pacific region: challenges and opportunities
    Thong MK, See-Toh Y, Hassan J, Ali J
    Genet Med, 2018 10;20(10):1114-1121.
    PMID: 30093710 DOI: 10.1038/s41436-018-0135-0
    Advances in genetic and genomic technology changed health-care services rapidly in low and middle income countries (LMICs) in the Asia-Pacific region. While genetic services were initially focused on population-based disease prevention strategies, they have evolved into clinic-based and therapeutics-oriented service. Many LMICs struggled with these noncommunicable diseases and were unprepared for the needs of a clinical genetic service. The emergence of a middle class population, the lack of regulatory oversight, and weak capacity-building in medical genetics expertise and genetic counseling services led to a range of genetic services of variable quality with minimal ethical oversight. Some of the current shortcomings faced include the lack of awareness of cultural values in genetic health care, the variable stages of socioeconomic development and educational background that led to increased demand and abuse of genetics, the role of women in society and the crisis of gender selection, the lack of preventive and care services for genetic and birth defects, the issues of gene ethics in medicine, and the lack of understanding of some religious controversies. These challenges provide opportunities for both developing and developed nations to work together to reduce the inequalities and to ensure a caring, inclusive, ethical, and cost-effective genetic service in the region.
    Matched MeSH terms: Genetic Counseling/trends*
  5. Training in clinical genetics and genetic counseling in Asia
    Cutiongco-de la Paz EM, Chung BH, Faradz SMH, Thong MK, David-Padilla C, Lai PS, et al.
    Am J Med Genet C Semin Med Genet, 2019 06;181(2):177-186.
    PMID: 31037827 DOI: 10.1002/ajmg.c.31703
    The status of training in clinical genetics and genetic counseling in Asia is at diverse stages of development and maturity. Most of the training programs are in academic training centers where exposure to patients in the clinics or in the hospital is a major component. This setting provides trainees with knowledge and skills to be competent geneticists and genetic counselors in a variety of patient care interactions. Majority of the training programs combine clinical and research training which provide trainees a broad and integrated approach in the diagnosis and management of patients while providing opportunities for research discoveries that can be translated to better patient care. The background on how the training programs in clinical genetics and genetic counseling in Asia evolved to their current status are described. Each of these countries can learn from each other through sharing of best practices and resources.
    Matched MeSH terms: Genetic Counseling
  6. Fulltext Global trends and themes in genetic counseling research
    Zakaria WNA, Yoon SY, Wijaya A, Ahmad AH, Zakaria R, Othman Z
    Eur J Hum Genet, 2023 Oct;31(10):1181-1184.
    PMID: 37142766 DOI: 10.1038/s41431-023-01371-3
    This article seeks to highlight the most recent trends and themes in genetic counseling that are of broad interest. A total of 3505 documents were published between 1952 and 2021, with a trend toward increase in paper/year. The most common documents are original articles (2515, 71.8%), followed by review articles (341, 9.7%). Journal of Genetic Counseling publishes the highest number of genetic counseling articles (587, 16.7%), followed by Clinical Genetics (103, 2.9%) and the South American Journal of Medical Genetics (95, 2.7%). Co-occurrence analysis revealed five research themes: genetic testing, cancer, genetic counselor, prenatal diagnosis, and psychiatry. The genetic counselor theme contained most of the recent keywords, including "covid-19," "underrepresented population," "service delivery models," "workforce," "disparities," "service delivery," "professional development," "cultural competence," "access," "diversity," "telemedicine," and "health literacy." Genetic counseling researchers may use these keywords to find topics pertinent to their future research and practice.
    Matched MeSH terms: Genetic Counseling
  7. Fulltext Genes, medicine and society: from paediatrics to genetic counselling and beyond
    Thong MK
    JUMMEC, 2012;15(2):1-8.
    MyJurnal
    The story of clinical genetics is a relatively new one, first spearheaded by paediatrics but increasingly, has taken root in all branches of medicine leading to ‘personalised medicine’. There are expectations that this revolution in genetics will pave the way to genomic medicine and a cure for all inherited disorders. The development of the field of Clinical Genetics and genetic counselling in Malaysia is still in its infancy. Using evidence-based data on genetic disorders such as birth defects, inborn errors of metabolism, genetic syndromes, neurological disorders and hereditary cancers, that hitherto have not been well documented in Malaysia, this review article will focus on findings and issues that will present a unique insight and opportunity to understanding the complex genetic counselling issues related to clinical genetics in Malaysia.
    Matched MeSH terms: Genetic Counseling
  8. Unexpected relevant role of gene mosaicism in patients with primary immunodeficiency diseases
    Mensa-Vilaró A, Bravo García-Morato M, de la Calle-Martin O, Franco-Jarava C, Martínez-Saavedra MT, González-Granado LI, et al.
    J Allergy Clin Immunol, 2019 Jan;143(1):359-368.
    PMID: 30273710 DOI: 10.1016/j.jaci.2018.09.009
    BACKGROUND: Postzygotic de novo mutations lead to the phenomenon of gene mosaicism. The 3 main types are called somatic, gonadal, and gonosomal mosaicism, which differ in terms of the body distribution of postzygotic mutations. Mosaicism has been reported occasionally in patients with primary immunodeficiency diseases (PIDs) since the early 1990s, but its real involvement has not been systematically addressed.

    OBJECTIVE: We sought to investigate the incidence of gene mosaicism in patients with PIDs.

    METHODS: The amplicon-based deep sequencing method was used in the 3 parts of the study that establish (1) the allele frequency of germline variants (n = 100), (2) the incidence of parental gonosomal mosaicism in families with PIDs with de novo mutations (n = 92), and (3) the incidence of mosaicism in families with PIDs with moderate-to-high suspicion of gene mosaicism (n = 36). Additional investigations evaluated body distribution of postzygotic mutations, their stability over time, and their characteristics.

    RESULTS: The range of allele frequency (44.1% to 55.6%) was established for germline variants. Those with minor allele frequencies of less than 44.1% were assumed to be postzygotic. Mosaicism was detected in 30 (23.4%) of 128 families with PIDs, with a variable minor allele frequency (0.8% to 40.5%). Parental gonosomal mosaicism was detected in 6 (6.5%) of 92 families with de novo mutations, and a high incidence of mosaicism (63.9%) was detected among families with moderate-to-high suspicion of gene mosaicism. In most analyzed cases mosaicism was found to be both uniformly distributed and stable over time.

    CONCLUSION: This study represents the largest performed to date to investigate mosaicism in patients with PIDs, revealing that it affects approximately 25% of enrolled families. Our results might have serious consequences regarding treatment and genetic counseling and reinforce the use of next-generation sequencing-based methods in the routine analyses of PIDs.

    Matched MeSH terms: Genetic Counseling
  9. Genetic counseling for patients and families with hereditary breast and ovarian cancer in a developing Asian country: an observational descriptive study
    Yoon SY, Thong MK, Taib NA, Yip CH, Teo SH
    Fam Cancer, 2011 Jun;10(2):199-205.
    PMID: 21318382 DOI: 10.1007/s10689-011-9420-7
    Genetic counseling (GC) and genetic testing are vital risk management strategies in hereditary breast and ovarian cancer (HBOC) syndromes. Hitherto, cancer genetic testing amongst Asians has been described only in developed and high-income Asian countries. We studied the uptake and acceptance of GC and genetic testing services to Asian BRCA carriers in a middle-income country. A total of 363 patients were tested by full sequencing and large rearrangement analysis of both BRCA1 and BRCA2 genes in the Malaysian Breast Cancer (MyBrCa) Genetic Study. Of these, 49 index patients (13.5%) were found to carry deleterious mutations. GC pre- and post- result disclosures were provided and these groups of patients and their families were studied. GC and genetic testing were accepted by 82% of Malaysian patients at high risk for HBOC syndromes. However, risk assessment was limited by large, geographically dispersed, often polygamous or polyandrous families, and the lack of complete cancer registry. Cultural taboos about cancer diagnoses, social marginalization and lack of regulatory control of genetic discrimination were significant concerns. Only 78% of index patients informed their families of their risks and 11% of relatives came forward when offered free counseling and testing. Even when GC and genetic testing are provided at no cost, there remain significant societal and regulatory barriers to effective cancer genetic services in this underserved Asian population. Families believe there is a need for regulatory protection against genetic discrimination. Further studies are needed in the area of increasing awareness about the potential benefits of GC and genetic testing in Asians.
    Matched MeSH terms: Genetic Counseling*
  10. A Report on Ten Asia Pacific Countries on Current Status and Future Directions of the Genetic Counseling Profession: The Establishment of the Professional Society of Genetic Counselors in Asia
    Laurino MY, Leppig KA, Abad PJ, Cham B, Chu YWY, Kejriwal S, et al.
    J Genet Couns, 2018 02;27(1):21-32.
    PMID: 28699126 DOI: 10.1007/s10897-017-0115-6
    The Professional Society of Genetic Counselors in Asia (PSGCA) was recently established as a special interest group of the Asia Pacific Society of Human Genetics. Fostering partnerships across the globe, the PSGCA's vision is to be the lead organization that advances and mainstreams the genetic counseling profession in Asia and ensures individuals have access to genetic counseling services. Its mission is to promote quality genetic counseling services in the region by enhancing practice and curricular standards, research and continuing education. The PSGCA was formally launched during the Genetic Counseling Pre-Conference Workshop held at the 11th Asia-Pacific Conference on Human Genetics in Hanoi, Viet Nam, September 16, 2015. The pre-conference workshop provided an opportunity for medical geneticists and genetic counselors from across 10 Asia Pacific countries to learn about the varied genetic counseling practices and strategies for genetic counseling training. This paper provides an overview of the current status and challenges in these countries, and proposed course of unified actions for the future of the genetic counseling profession.
    Matched MeSH terms: Genetic Counseling/trends*
  11. Advancing Global Precision Medicine: An Overview of Genomic Testing and Counseling Services in Malaysia
    Balasopoulou A, Mooy FM, Baker DJ, Mitropoulou C, Skoufas E, Bulgiba A, et al.
    OMICS, 2017 12;21(12):733-740.
    PMID: 29173101 DOI: 10.1089/omi.2017.0136
    Precision medicine, genomic and diagnostic services are no longer limited to developed countries. This broadening in geography of biomarker applications and omics diagnostics also demands empirical study of implementation, diagnostic testing, and counseling practices in the field. For example, the Malaysian population has large ethnic diversity and high prevalence of genetic disorders such as hemoglobinopathies and metabolic disorders. Increased morbidity and mortality from such diseases have a direct impact on society and health system sustainability and for this, decision-making becomes of outmost importance. We report here on our findings on the landscape of genomic testing and genetic counseling services in Malaysia. We first defined the framework of all Malaysian stakeholders that offer genomics services and next, we identified the related information gaps, as depicted through the service providers' online websites. Our research framework revealed that there is a very diverse spectrum of genomics services in Malaysia, in which wet- and dry-laboratory services integrate. Moreover, we identify the current gaps and possible remedies to improve the quality of genomic and predictive analytics, not to mention considerations to ensure robust ethics and responsible innovation. To our knowledge, this is the first such study to be performed for a Southeast Asian country. Our genomics and precision medicine services mapping strategy presented in this study may serve as a model for field assessment at regional, national, and international levels as precision medicine is expanding globally and new governance challenges and opportunities continue to emerge for smart implementation science.
    Matched MeSH terms: Genetic Counseling/statistics & numerical data
  12. Fulltext Psychosocial outcome and health behaviour intent of breast cancer patients with BRCA1/2 and PALB2 pathogenic variants unselected by a priori risk
    Padmanabhan H, Hassan NT, Wong SW, Lee YQ, Lim J, Hasan SN, et al.
    PLoS One, 2022;17(2):e0263675.
    PMID: 35167615 DOI: 10.1371/journal.pone.0263675
    There is an increasing number of cancer patients undertaking treatment-focused genetic testing despite not having a strong family history or high a priori risk of being carriers because of the decreasing cost of genetic testing and development of new therapies. There are limited studies on the psychosocial outcome of a positive result among breast cancer patients who are at low a priori risk, particularly in women of Asian descent. Breast cancer patients enrolled under the Malaysian Breast Cancer Genetic Study between October 2002 and February 2018 were tested for BRCA1, BRCA2 and PALB2 genes. All 104 carriers identified were invited by a research genetic counsellor for result disclosure. Of the 104 carriers, 64% (N = 66) had low a priori risk as determined by PENN II scores. Psychosocial, risk perception and health behaviour measures survey were conducted at baseline (pre-result disclosure), and at two to six weeks after result disclosure. At baseline, younger carriers with high a priori risk had higher Cancer Worry Scale scores than those with low a priori risk but all scores were within acceptable range. Around 75% and 55% of high a priori risk carriers as well as 80% and 67% of low a priori risk carriers had problems in the "living with cancer" and "children" psychosocial domains respectively. All carriers regardless of their a priori risk demonstrated an improved risk perception that also positively influenced their intent to undergo risk management procedures. This study has shown that with sufficient counselling and support, low a priori risk carriers are able to cope psychologically, have improved perceived risk and increased intent for positive health behaviour despite having less anticipation from a family history prior to knowing their germline carrier status.
    Matched MeSH terms: Genetic Counseling/psychology*
  13. Fulltext The Global State of the Genetic Counseling Profession
    Abacan M, Alsubaie L, Barlow-Stewart K, Caanen B, Cordier C, Courtney E, et al.
    Eur J Hum Genet, 2019 Feb;27(2):183-197.
    PMID: 30291341 DOI: 10.1038/s41431-018-0252-x
    The profession of genetic counseling (also called genetic counselling in many countries) began nearly 50 years ago in the United States, and has grown internationally in the past 30 years. While there have been many papers describing the profession of genetic counseling in individual countries or regions, data remains incomplete and has been published in diverse journals with limited access. As a result of the 2016 Transnational Alliance of Genetic Counseling (TAGC) conference in Barcelona, Spain, and the 2017 World Congress of Genetic Counselling in the UK, we endeavor to describe as fully as possible the global state of genetic counseling as a profession. We estimate that in 2018 there are nearly 7000 genetic counselors with the profession established or developing in no less than 28 countries.
    Matched MeSH terms: Genetic Counseling/statistics & numerical data*
  14. A single centre study on birth of children with transfusion-dependent thalassaemia in Malaysia and reasons for ineffective prevention
    Ngim CF, Ibrahim H, Lai NM, Ng CS
    Prenat Diagn, 2015 Jan;35(1):51-9.
    PMID: 25156332 DOI: 10.1002/pd.4484
    We aimed to identify factors contributing to ineffective prevention of thalassaemia in Malaysia by studying events leading to the births of children with transfusion-dependent thalassaemia (TDT) including their parents' reproductive choices.
    Matched MeSH terms: Genetic Counseling/standards
  15. Genotype-Phenotype Correlation of β-Thalassemia in Malaysian Population: Toward Effective Genetic Counseling
    Abdullah UYH, Ibrahim HM, Mahmud NB, Salleh MZ, Teh LK, Noorizhab MNFB, et al.
    Hemoglobin, 2020 May;44(3):184-189.
    PMID: 32586164 DOI: 10.1080/03630269.2020.1781652
    Effective prevention of β-thalassemia (β-thal) requires strategies to detect at-risk couples. This is the first study attempting to assess the prevalence of silent β-thal carriers in the Malaysian population. Hematological and clinical parameters were evaluated in healthy blood donors and patients with β-thal trait, Hb E (HBB: c.79G>A)/β-thal and β-thal major (β-TM). β-Globin gene sequencing was carried out for 52 healthy blood donors, 48 patients with Hb E/β-thal, 34 patients with β-TM and 38 patients with β-thal trait. The prevalence of silent β-thal carrier phenotypes found in 25.0% of healthy Malaysian blood donors indicates the need for clinician's awareness of this type in evaluating β-thal in Malaysia. Patients with β-TM present at a significantly younger age at initial diagnosis and require more blood transfusions compared to those with Hb E/β-thal. The time at which genomic DNA was extracted after blood collection, particularly from patients with β-TM and Hb E/β-thal, was found to be an important determinant of the quality of the results of the β-globin sequencing. Public education and communication campaigns are recommended as apparently healthy individuals have few or no symptoms and normal or borderline hematological parameters. β-Globin gene mutation characterization and screening for silent β-thal carriers in regions prevalent with β-thal are recommended to develop more effective genetic counseling and management of β-thal.
    Matched MeSH terms: Genetic Counseling*
  16. α-thalassemia-associated hydrops fetalis: A rare cause of thyrotoxic cardiomyopathy
    Tumian NR, Wong M, Wong CL
    J Obstet Gynaecol Res, 2015 Jun;41(6):967-70.
    PMID: 25510540 DOI: 10.1111/jog.12648
    α°-thalassemia is a well-known cause of hydrops fetalis in South-East Asia and can be detected in utero. We report a very rare case of thyrotoxic cardiomyopathy associated with hyperplacentosis secondary to α°-thalassemia-associated hydrops fetalis. A 22-year-old primigravida with microcytic anemia presented at 27 weeks' gestation with pre-eclampsia, hyperthyroidism and cardiac failure. Serum β-human chorionic gonadotrophin was markedly elevated and abdominal ultrasound revealed severe hydropic features and enlarged placenta. Serum β-human chorionic gonadotrophin, cardiac function and thyroid function tests normalized after she delivered a macerated stillbirth. Histopathology of the placenta showed hyperplacentosis. Blood DNA analysis revealed that both patient and husband have the α°-thalassemia trait. This case illustrates a very atypical presentation of α°-thalassemia-associated hydrops fetalis and the importance of early prenatal diagnosis of α-thalassemia in women of relevant ethnic origin with microcytic anemia so that appropriate genetic counseling can be provided to reduce maternal morbidity and the incidence of hydrops fetalis.
    Matched MeSH terms: Genetic Counseling
  17. Diagnosis and management of Duchenne muscular dystrophy in a developing country over a 10-year period
    Thong MK, Bazlin RI, Wong KT
    Dev Med Child Neurol, 2005 Jul;47(7):474-7.
    PMID: 15991868
    Clinical data on Duchenne muscular dystrophy (DMD) are lacking in developing countries. The objective of this study was to delineate the demographic characteristics, investigations, and outcome of 21 Malaysian males diagnosed with DMD over a period of 10 years. Mean age presentation was 3 years 8 months (SD 23mo; range 10 to 84mo), mean duration from first presentation to diagnosis was 3y 7mo (SD 26mo; range 5 to 84) and the mean age for loss of ambulation was 11 years (SD 25mo; range 102 to 168). There was family history of DMD in five of the 21 patients. Muscle biopsy showed confirmatory findings of DMD in the 16 patients tested. Molecular genetic analysis showed dystrophin gene deletions in 11 of these 16 patients. Four and seven of the students stopped schooling and had learning difficulties, respectively; only nine had satisfactory school performances. Eight out of 14 patients evaluated were classified as having severe to total dependency levels on the modified Barthel Index for activities of daily living assessment. DMD is associated with significant medical and social needs for a developing country such as Malaysia. Earlier referral, genetic counselling, and provision of support and rehabilitative services are the main priorities.
    Matched MeSH terms: Genetic Counseling
  18. Fulltext Thalassaemia in Malaysia: a strategy for prevention
    Ainoon O, Cheong SK
    Malays J Pathol, 1994 Jun;16(1):23-7.
    PMID: 16329572
    In Malaysia, alpha-thalassaemia, beta-thalassaemia, haemoglobin (Hb) E, deltabeta-thalassaemia and Hb Constant Spring are prevalent. It has been estimated that 1 in 4 persons carries one of the above genetic abnormalities. In clinical practice, the major problems are: Hb Bart's hydrops fetalis (homozygous alpha(o)thalassaemia), homozygous 3(o)-thalassaemia, E-alpha thalassaemia and HbH disease. The laboratory procedures for diagnosis are standardised and the molecular basis of most of these genetic abnormalities are characterised. Thus it is possible to formulate a strategy for the detection and prevention of these disorders. The steps include the setting-up of population screening and genetic counselling service for the affected individuals, Society of Thalassaemias for public education and group support, and prenatal diagnosis with selective abortion of affected pregnancies. We embarked on such a programme between 1988 and 1992 in Kuala Lumpur General Hospital and hope to kindle similar effort in other state hospitals.
    Matched MeSH terms: Genetic Counseling
  19. Siriraj I Gγ(Aγδβ)0-thalassaemia causing severe thalassaemia intermedia in compound heterozygous state with IVS1-1(G→T) mutation
    Wong YY, Alauddin H, Raja Sabudin RZA, Ithnin A, Jalil N, Abdul Latiff Z, et al.
    Malays J Pathol, 2021 Apr;43(1):95-100.
    PMID: 33903312
    The Siriraj I Gγ(Aγδβ)0-thalassaemia is a novel mutation involving a 118kb deletion of the β-globin gene cluster. It was first reported in 2012 in two unrelated families from the southern part of Thailand. The carriers in the heterozygous state are clinically asymptomatic. Nonetheless, its complex interaction with other β-thalassaemia could give rise to different clinical phenotypes, ranging from mild thalassaemia intermedia to thalassaemia major. We report here a case of a six-year-old Malay boy, presented with pallor, growth failure and hepatosplenomegaly. His haemoglobin at presentation was 9.2g/dL with a mean cell haemoglobin of 22.6pg and a mean cell volume of 69.9fl. His peripheral blood smear showed features of thalassaemia intermedia. Haemoglobin (Hb) analysis revealed markedly raised Hb F (83%), normal HbA2 levels and absent HbA. Deoxyribonucleic acid (DNA) analysis showed compound heterozygous IVS1-1 (G→T) β-globin gene mutation and Siriraj I Gγ(Aγδβ)0-deletion (genotype βIVS1-1/ β Siriraj I deletion). Both his father and elder sister are carriers of Siriraj I Gγ(Aγδβ)0-thalassaemia while his mother carries IVS1-1 (G→T) gene mutation. Clinically, the patient is transfusion dependent on six weekly regime. To the best of our knowledge, this is the first reported case in Malaysia involving unique Siriraj I Gγ(Aγδβ)0-thalassaemia and IVS1-1 (G→T) in a compound heterozygous state. In summary, detection of Siriraj I Gγ(Aγδβ)0-thalassaemia is essential as this deletion can lead to severe disease upon interaction with a β-thalassemia point mutation as demonstrated in our case. The establishment of effective carrier screening and genetic counselling is important to prevent its adverse consequences.
    Matched MeSH terms: Genetic Counseling
  20. Fulltext Differential outcomes in an extended family with constitutional t(11;22)(q23.3;q11.2)
    Kee SK, See VH, Chia P, Tan WC, Tien SL, Lim ST
    J Pediatr Genet, 2013 Mar;2(1):37-41.
    PMID: 27625838 DOI: 10.3233/PGE-13046
    The t(11;22) rearrangement is the most common recurrent familial reciprocal translocation in man. Heterozygote carriers are phenotypically normal but are at risk of subfertility in the male, miscarriages, and producing chromosomally unbalanced offspring. The unbalanced progeny usually results from an extra der(22) chromosome resulting from a 3:1 malsegregation. We present here a family with t(11;22). Of six siblings, three were found to be carriers following prenatal diagnosis of the proband fetus. Neither of the two married carrier siblings have a live born child. In keeping with the prevailing knowledge of the pregnancy outcomes of heterozygote carriers, between the siblings they had recurrent miscarriages, a fetus with a +der(22) chromosome, and other subfertility issues resulting in multiple failed in vitro fertilization cycles with preimplantation genetic diagnosis. However, unlike the siblings, their extended family comprising their heterozygote translocation mother, married aunts and an uncle had normal fertility and a lack of a history of miscarriages or an abnormal child. The differing outcomes may be related to the male partners having additional semen anomalies which may further exacerbate problems associated with the t(11;22). Because the t(11;22) rearrangement tends to run in families, it is recommended that chromosome studies are offered to family members of an affected relative as an option, and provide them with appropriate genetic counseling so that they will have the necessary information with regard to their risk for subfertility, miscarriages, and production of viable unbalanced offspring. Follow-up prenatal diagnosis should also be offered to affected expectant family members, especially after preimplantation genetic diagnosis.
    Matched MeSH terms: Genetic Counseling
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