Meow-Keong Thong

Meow-Keong Thong
University of Malaya | UM · Department of Paediatrics

MBBS, MPaeds, MD, FHGSA (Clinical Genetics) FASc

About

149
Publications
43,140
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Introduction
M-K Thong is a Professor of Paediatrics and board-certified consultant clinical geneticist at the University of Malaya Medical Centre, Malaysia, providing genetic services and genetic counselling to paediatric and adult patients with hereditary conditions. He is engaged in medical education and research in birth defects, inborn errors of metabolism, cancer genetics and genetic counselling. He was a past President of the Asia-Pacific Society of Human Genetics, and the current President of the College of Paediatrics, Academy of Medicine of Malaysia
Additional affiliations
June 1995 - present
University of Malaya
Position
  • Professor (Full)
January 1995 - present
University of Malaya
Position
  • Professor (Full)

Publications

Publications (149)
Article
Cascade testing for families with BRCA pathogenic variants is important to identify relatives who are carriers. These relatives can benefit from appropriate risk management and preventative strategies arising from an inherited increased risk of breast, ovarian, prostate, melanoma, and pancreatic cancers. Cascade testing has the potential to enable...
Article
Full-text available
To address inborn errors of immunity (IEI) which were underdiagnosed in resource-limited regions, our centre developed and offered free genetic testing for the most common IEI by Sanger sequencing (SS) since 2001. With the establishment of The Asian Primary Immunodeficiency (APID) Network in 2009, the awareness and definitive diagnosis of IEI were...
Article
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Neural tube defects (NTDs) are common birth defects with a complex genetic etiology. Mouse genetic models have indicated a number of candidate genes, of which functional mutations in some have been found in human NTDs, usually in a heterozygous state. This study focuses on Ephs-ephrins as candidate genes of interest owing to growing evidence of the...
Article
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Genomic medicine aims to improve health using the individual genomic data of people to inform care. While clinical utility of genomic medicine in many monogenic, Mendelian disorders is amply demonstrated, clinical utility is less evident in polygenic traits, e.g., coronary artery disease or breast cancer. Polygenic risk scores (PRS) are subsets of...
Article
With the advent of poly‐ADP‐ribose polymerase inhibitor (PARPi) therapies, the focus of genetic testing for breast, ovarian, and other cancers has shifted from risk management to treatment decision‐making in high‐resource settings. Due to the shortage of genetic counselors worldwide, alternative ways of delivering genetic counseling have been explo...
Article
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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...
Preprint
Full-text available
Neural tube defects (NTDs) are among the most common of birth defects. Despite the many gene candidates identified in certain population; none have thus far been regarded as compelling enough as a candidate for different populations. As candidate genes for NTDs, this study focussed on Ephs and ephrins owing to growing evidence for the role of this...
Article
Background Identifying patients with BRCA mutations is clinically important to inform on the potential response to treatment and for risk management of patients and their relatives. However, traditional referral routes may not meet clinical needs, and therefore, mainstreaming cancer genetics has been shown to be effective in some high-income and hi...
Article
Full-text available
The vast majority of studies assessing communication of BRCA1/2 results with relatives and family uptake of BRCA1/2 testing have been conducted in Western societies, and a dearth of studies have been conducted in Asia among relatives of diverse carriers of pathogenic BRCA1/2 germline variants. This study aimed to present rates of BRCA1/2 result dis...
Article
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Rubinstein-Taybi syndrome (RSTS) is an autosomal dominant disorder, caused by loss-of-function variants in CREBBP or EP300. Affected individuals present with distinctive craniofacial features, broad thumbs and/or halluces, and intellectual disability. RSTS phenotype has been well characterized in individuals of European descent but not in other pop...
Article
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Background: Thalassaemia is a recessively-inherited blood disorder that leads to anaemia of varying severity. In those affected by the more severe forms, regular blood transfusions are required which may lead to iron overload. Accumulated iron from blood transfusions may be deposited in vital organs including the heart, liver and endocrine organs...
Article
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Objective Rare diseases are often underdiagnosed, and their management is frequently complicated by a lack of access to treatment and information about the diseases. To allow for better policy planning, we sought to examine the current status of managing rare diseases in Malaysia. Methods This study was conducted in two phases. In the first phase,...
Article
Full-text available
Neural tube defects (NTDs) are congenital anomalies resulting from the failure of neural tube closure during embryogenesis. The precise molecular mechanisms underlying this multifactorial disease is poorly understood, although single nucleotide polymorphisms in genes involved in the one-carbon metabolism cycle are believed to contribute towards NTD...
Article
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Turner syndrome (TS) is a common multiple congenital anomaly syndrome resulting from complete or partial absence of the second X chromosome. In this study, we explore the phenotype of TS in diverse populations using clinical examination and facial analysis technology. Clinical data from 78 individuals and images from 108 individuals with TS from 19...
Article
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Background: Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disease due to N-acetylgalactosamine-6-sulfatase (GALNS) deficiency. It results in accumulation of the glycosaminoglycans, keratan sulfate and chondroitin-6-sulfate, leading to skeletal and other systemic impairments. Data on MPS IVA in Asian populations ar...
Article
Congenital myasthenic syndrome (CMS) is a heterogeneous group of inherited disorder which does not associate with anti-acetylcholine receptor (AChR) antibody. The presence of AChR autoantibody is pathogenic and highly sensitive and specific for autoimmune myasthenia gravis (MG). We describe 2 children from unrelated families who presented with hypo...
Article
Reproductive carrier screening started in some countries in the 1970s for hemoglobinopathies and Tay‐Sachs disease. Cystic fibrosis carrier screening became possible in the late 1980s and with technical advances, screening of an ever increasing number of genes has become possible. The goal of carrier screening is to inform people about their risk o...
Article
Background Identification of germline BRCA mutations in ovarian cancer patients allows clinicians to make treatment decisions and manage risks. Due to the lack of genetic counsellors, clinical geneticists and awareness among clinicians, there is minimal testing regionally. Mainstreaming genetic counselling may improve this access. This study aims t...
Article
Infantile neuroaxonal dystrophy 1 (INAD) (OMIM #256600) is a rare infantile onset neurodegenerative disease characterised by neuroregression and hypotonia, evolving into generalized spasticity, blindness and dementia. We report our diagnostic approach of a pair of siblings with psychomotor regression, hypotonia, optic atrophy and auditory neuropath...
Article
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Limited data are available on the survival of patients with Down syndrome and congenital heart disease (CHD) from middle-income countries. This retrospective cohort study was performed to determine the trends in the prevalence and survival of such patients born from January 2006 to December 2015 in Malaysia. Among 754 patients with Down syndrome, 4...
Article
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For this study, an educational computer game called Ecoship Endeavour was designed based on the guidelines of the Inquiry, Communication, Mystery, Decision making, Challenge and Rewards (ICMDCR) framework to help facilitate critical thinking skills in students. To examine the effectiveness of the proposed Digital Game-Based Learning (DGBL) approach...
Article
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In the era of personalized and genomic medicine, awareness of patients with rare diseases is increasing as new approaches to diagnosis and treatment are developed. This study examined perceived barriers experienced by families with rare diseases and explored possible differences between participants in Malaysia and California, USA. The study involv...
Article
Aim Evaluation of impaired quality of life (QOL) of Malaysian children with tuberous sclerosis complex (TSC) and its possible risk factors. Method Cross-sectional study on 68 parents of Malaysian children aged 2–18 years with TSC. QOL was assessed using proxy-report Paediatric Quality of Life Inventory (PedsQL) V.4.0, and scores compared with thos...
Article
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Digital game-based learning (DGBL) has been perceived as an engaging teaching approach to foster students’ learning and motivation. There are different opinions about the potential benefits of gaming on students’ academic achievements, motivation, and skills in science courses due to the lack of empirical evidence and mixed results. To address this...
Article
Putting together the reports in this issue that come from a representation of the different countries in Asia presents an opportunity to share the unique story of the Asia Pacific Society of Human Genetics (APSHG), which has provided the authors of many of these articles. This paper, authored by the Past Presidents of the Society, shares glimpses o...
Article
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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 geneti...
Article
Clinical ethics consultation service remains undeveloped in developing countries. It is recognised that its introduction poses challenges. Malaysia, a multicultural society with diverse religions, values and perceptions further complicate the introduction of formal clinical ethics consultation service. Clinicians attending a national congress works...
Article
The United Nations General Assembly adopted the 2030 Agenda for Sustainable Development in November 2015 which included a set of 17 measurable “sustainable development goals” (SDGs). The SDGs included targets to end preventable deaths of newborns and children under 5 years of age by 2030, universal health care coverage, reduction of premature morta...
Article
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Cornelia de Lange syndrome (CdLS) is a dominant multisystemic malformation syndrome due to mutations in five genes—NIPBL, SMC1A, HDAC8, SMC3, and RAD21. The characteristic facial dysmorphisms include microcephaly, arched eyebrows, synophrys, short nose with depressed bridge and anteverted nares, long philtrum, thin lips, micrognathia, and hypertric...
Article
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Objectives: The Neural Tube Defects Research Group of University of Malaya was approached to analyze a tablet named TELSE, which may have resulted in a baby born with central nervous system malformation at the University of Malaya Medical Centre. In this animal experimental study, we investigated the content of TELSE and exposure of its contents t...
Article
Background: Germline BRCA1 or BRCA2 pathogenic variants in ovarian cancer patients may be informative in risk management and treatment, with the advent of poly(ADP-ribose) polymerase inhibitors. In the era of precision medicine, companion diagnostics for BRCA1 and BRCA2 genes have been featured as a strategy in the Malaysia National Strategic Plan...
Article
Full-text available
Background Breast cancer risk factors have been examined extensively in Western setting and more developed Asian cities/countries. However, there are limited data on developing Asian countries. The purpose of this study was to examine breast cancer risk factors and the change of selected risk factors across birth cohorts in Malaysian women. Method...
Data
Survey questions. This file contains the questionnaire items used in this study. (DOCX)
Article
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...
Article
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Crouzon syndrome exhibits considerable phenotypic heterogeneity, in the aetiology of which genetics play an important role. FGFR2 mediates extracellular signals into cells and the mutations in the FGFR2 gene cause this syndrome occurrence. Activated FGFs/FGFR2 signaling disrupts the balance of differentiation, cell proliferation, and apoptosis via...
Article
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Williams–Beuren syndrome (WBS) is a common microdeletion syndrome characterized by a 1.5Mb deletion in 7q11.23. The phenotype of WBS has been well described in populations of European descent with not as much attention given to other ethnicities. In this study, individuals with WBS from diverse populations were assessed clinically and by facial ana...
Article
The cover image, by Paul Kruszka et al., is based on the Original Article Williams‐Beuren Syndrome in Diverse Populations, DOI: 10.1002/ajmg.a.38672
Article
Objective: Previous studies showed that offering BRCA mutation testing to population subgroups at high risk of harbouring the mutation may be cost effective, yet no evidence is available for low- or middle-income countries (LMIC) and in Asia. We estimated the cost effectiveness of BRCA mutation testing in early-stage breast cancer patients with hi...
Article
Objective: To study the audiological outcome and early screening of pre-school going children with craniosynostosis under follow-up at the University of Malaya Medical Center(UMMC), Kuala Lumpur, Malaysia over a 10 year period. Methods: A retrospective descriptive cohort study on the audiological findings detected during the first hearing assessme...
Article
Full-text available
Background The aim of this study is to review the medical history of patients with spina bifida, encompassing both aperta and occulta types born between the years 2003 until 2016, spanning a 13-year time period. We assessed each patient and maternal parent information, details of the defects, and conditions associated with the primary defect. We al...
Article
Full-text available
Background Thalassaemia is a recessively-inherited blood disorder that leads to anaemia of varying severity. In those affected by the more severe forms, regular blood transfusions are required which may lead to iron overload. Accumulated iron from blood transfusions may be deposited in vital organs including the heart, liver and endocrine organs su...
Article
Full-text available
The cover image, by Paul Kruszka et al., is based on the Original Article Noonan Syndrome in Diverse Populations, DOI: 10.1002/ajmg.a.38362. Design Credit: Darryl Leja.
Article
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Background Severe combined immunodeficiency (SCID) is fatal unless treated with hematopoietic stem cell transplant. Delay in diagnosis is common without newborn screening. Family history of infant death due to infection or known SCID (FH) has been associated with earlier diagnosis. Objective The aim of this study was to identify the clinical featu...
Data
Distribution of age at diagnosis and time to diagnosis of patients with genetic diagnosis (n = 83). Distribution of age at diagnosis of patients with chronic diarrhea (A), severe infections (B), and lymphopenia (C) and distribution of time to diagnosis of patients with chronic diarrhea (D) and lymphopenia (E).
Article
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...
Article
Full-text available
Noonan syndrome (NS) is a common genetic syndrome associated with gain of function variants in genes in the Ras/MAPK pathway. The phenotype of NS has been well characterized in populations of European descent with less attention given to other groups. In this study, individuals from diverse populations with NS were evaluated clinically and by facia...
Article
PurposeGenome-wide association studies (GWAS) have been instrumental to our understanding of the genetic risk determinants of complex traits. A common challenge in GWAS is the interpretation of signals, which are usually attributed to the genes closest to the polymorphic markers that display the strongest statistical association. Naturally occurrin...
Article
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Introduction: MicroRNAs (miRNAs) are short RNA molecules of approximately 22 nucleotides that function as post-transcriptional regulators of gene expression. They are expressed in a tissue-specific manner and show different expression patterns in development and disease; hence, they can potentially act as disease-specific biomarkers. Several miRNA...
Article
The urea cycle disorder carbamoyl phosphate synthetase I deficiency is an important differential diagnosis in the encephalopathic neonate. This intoxication type inborn error of metabolism often leads to neonatal death or severe and irreversible damage of the central nervous system, even despite appropriate treatment. Timely diagnosis is crucial, b...
Article
DS) is the most common microdeletion syndrome and is underdiagnosed in diverse populations. This syndrome has a variable phenotype and affects multiple systems, making early recognition imperative. In this study, individuals from diverse populations with 22q11.2 DS were evaluated clinically and by facial analysis technology. Clinical information fr...
Article
The cover image, by Paul Kruszka et al., is based on the Original Article 22q11.2 deletion syndrome in diverse populations, DOI: 10.1002/ajmg.a.38199. Individual images are property of the National Human Genome Research Institute and are in the public domain.
Article
Full-text available
Background and purpose Drug administration errors are more likely to reach the patient than other medication errors. The main aim of this study was to determine whether the sharing of information on drug administration errors among health care providers would reduce such problems. Patients and methods This study involved direct, undisguised observ...
Article
Full-text available
Objective: The lack of epidemiological data and molecular diagnostic services in Malaysia has hampered the setting-up of a comprehensive management plan for patients with myotonic dystrophy type 1 (DM1), leading to delayed diagnosis, treatment and support for patients and families. The aim of this study was to estimate the prevalence of DM1 in the...
Article
Full-text available
Down syndrome is the most common cause of cognitive impairment and presents clinically with universally recognizable signs and symptoms. In this study, we focus on exam findings and digital facial analysis technology in individuals with Down syndrome in diverse populations. Photos and clinical information were collected on 65 individuals from 13 co...
Article
We report the first known ethnic Malay patient with laminin alpha-2 (merosin) deficiency (MDC1A), a subtype of congenital muscular dystrophy (CMD)as a result of novel LAMA2 gene mutations. The 21-month-old female presented with hypotonia at birth and gross motor delay of her distal lower limbs. Physical examination showed generalised hypotonia, hyp...