TY - JOUR
T1 - Title-molecular diagnostics of dystrophinopathies in Sri Lanka towards phenotype predictions
T2 - an insight from a South Asian resource limited setting
AU - Wijekoon, Nalaka
AU - Gonawala, Lakmal
AU - Ratnayake, Pyara
AU - Liyanage, Roshan
AU - Amaratunga, Dhammika
AU - Hathout, Yetrib
AU - Steinbusch, Harry W.M.
AU - Dalal, Ashwin
AU - Hoffman, Eric P.
AU - de Silva, K. Ranil D.
N1 - Funding Information:
The Corresponding author in Sri Lanka received funding from the Muscular Dystrophy Association Washington DC, USA (Grant Number FMS/7090/2010), The World Health Organization (WHO) (Grant Number 2010/81594-0), the World Class University Grant Project (University of Sri Jayewardenepura, Sri Lanka; Grant Numbers WCUP/Ph.D./19/2013 and WCUP/Ph.D./19B 2013), the Ministry of Primary Industries, Sri Lanka (Grant Number SP/CIN/2016/02, the University of Sri Jayewardenepura (Grant Numbers ASP/06/RE/2010/07, ASP/06/RE/2012/18, ASP/06/RE/2013/28), General Sir John Kotelawala Defence University, Sri Lanka (Grant Numbers KDU/RG/2021/CARE/005 and KDU/RG/2021/CARE/006), and the Interdisciplinary Center for Innovation in Biotechnology and Neuroscience, University of Sri Jayewardenepura (ICIBN/ USJ). Equipment was donated by the National Institutes of Health (Bethesda, MD, USA) through IBRO-APRC and by the Chinese Neuroscience Society. Moreover, the corresponding author has received funding from IBRO-APRC and the International Society for Neurochemistry (ISN) for international training scholarships for postgraduates and to conduct Neuroscience workshops in Sri Lanka.
Publisher Copyright:
© 2024, The Author(s).
PY - 2024/12/1
Y1 - 2024/12/1
N2 - Background: The phenotype of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) patients is determined by the type of DMD gene variation, its location, effect on reading frame, and its size. The primary objective of this investigation was to determine the frequency and distribution of DMD gene variants (deletions/duplications) in Sri Lanka through the utilization of a combined approach involving multiplex polymerase chain reaction (mPCR) followed by Multiplex Ligation Dependent Probe Amplification (MLPA) and compare to the international literature. The current consensus is that MLPA is a labor efficient yet expensive technique for identifying deletions and duplications in the DMD gene. Methodology: Genetic analysis was performed in a cohort of 236 clinically suspected pediatric and adult myopathy patients in Sri Lanka, using mPCR and MLPA. A comparative analysis was conducted between our findings and literature data. Results: In the entire patient cohort (n = 236), mPCR solely was able to identify deletions in the DMD gene in 131/236 patients (DMD-120, BMD-11). In the same cohort, MLPA confirmed deletions in 149/236 patients [DMD-138, BMD -11]. These findings suggest that mPCR has a detection rate of 95% (131/138) among all patients who received a diagnosis. The distal and proximal deletion hotspots for DMD were exons 45–55 and 6–15. Exon 45–60 identified as a novel in-frame variation hotspot. Exon 45–59 was a hotspot for BMD deletions. Comparisons with the international literature show significant variations observed in deletion and duplication frequencies in DMD gene across different populations. Conclusion: DMD gene deletions and duplications are concentrated in exons 45–55 and 2–20 respectively, which match global variation hotspots. Disparities in deletion and duplication frequencies were observed when comparing our data to other Asian and Western populations. Identified a 95% deletion detection rate for mPCR, making it a viable initial molecular diagnostic approach for low-resource countries where MLPA could be used to evaluate negative mPCR cases and cases with ambiguous mutation borders. Our findings may have important implications in the early identification of DMD with limited resources in Sri Lanka and to develop tailored molecular diagnostic algorithms that are regional and population specific and easily implemented in resource limited settings.
AB - Background: The phenotype of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) patients is determined by the type of DMD gene variation, its location, effect on reading frame, and its size. The primary objective of this investigation was to determine the frequency and distribution of DMD gene variants (deletions/duplications) in Sri Lanka through the utilization of a combined approach involving multiplex polymerase chain reaction (mPCR) followed by Multiplex Ligation Dependent Probe Amplification (MLPA) and compare to the international literature. The current consensus is that MLPA is a labor efficient yet expensive technique for identifying deletions and duplications in the DMD gene. Methodology: Genetic analysis was performed in a cohort of 236 clinically suspected pediatric and adult myopathy patients in Sri Lanka, using mPCR and MLPA. A comparative analysis was conducted between our findings and literature data. Results: In the entire patient cohort (n = 236), mPCR solely was able to identify deletions in the DMD gene in 131/236 patients (DMD-120, BMD-11). In the same cohort, MLPA confirmed deletions in 149/236 patients [DMD-138, BMD -11]. These findings suggest that mPCR has a detection rate of 95% (131/138) among all patients who received a diagnosis. The distal and proximal deletion hotspots for DMD were exons 45–55 and 6–15. Exon 45–60 identified as a novel in-frame variation hotspot. Exon 45–59 was a hotspot for BMD deletions. Comparisons with the international literature show significant variations observed in deletion and duplication frequencies in DMD gene across different populations. Conclusion: DMD gene deletions and duplications are concentrated in exons 45–55 and 2–20 respectively, which match global variation hotspots. Disparities in deletion and duplication frequencies were observed when comparing our data to other Asian and Western populations. Identified a 95% deletion detection rate for mPCR, making it a viable initial molecular diagnostic approach for low-resource countries where MLPA could be used to evaluate negative mPCR cases and cases with ambiguous mutation borders. Our findings may have important implications in the early identification of DMD with limited resources in Sri Lanka and to develop tailored molecular diagnostic algorithms that are regional and population specific and easily implemented in resource limited settings.
KW - Dystrophin
KW - Muscular Dystrophies
KW - Mutations
KW - South Asia
U2 - 10.1186/s40001-023-01600-x
DO - 10.1186/s40001-023-01600-x
M3 - Article
SN - 0949-2321
VL - 29
JO - European Journal of Medical Research
JF - European Journal of Medical Research
IS - 1
M1 - 37
ER -