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Decade-long Application of Preimplantation Genetic Testing for DMD/BMD: Analysis of Five Clinical Strategies and Embryo Recombination Patterns

Overview
Journal Hum Genet
Specialty Genetics
Date 2025 Feb 19
PMID 39969580
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Abstract

This study aimed to find the most effective PGT-M strategy for Duchenne muscular dystrophy/Becker muscular dystrophy (DMD/BMD), and to reduce misdiagnosis caused by embryo recombination in DMD. A retrospective study was performed by analyzing 158 PGT-M cycles for DMD/BMD in Reproductive and Genetic Hospital of CITIC-Xiangya between 2009 and 2023. Patients' backgrounds were collected. The effectiveness and safety for five different PGT-M strategies (1-5), including mutation testing from cleavage or trophoblast ectoderm (TE) cells and additional linkage analysis post-TE cell amplification, were analyzed. The embryonic recombination events were assessed for these cycles. Mutation analysis showed that 62.4% of the 125 families had DMD deletions, 16.0% had duplications, and 21.6% had single nucleotide variants (SNVs). Among 125 families, 104 (83.2%) had previously affected fetus or offspring. The highest diagnosis rate (99.56%) was achieved with Strategy 5, which combined mutation testing with SNP-based linkage analysis in TE cells. This strategy 5 also demonstrated an advantage in cases with recombination near the mutation. An intragenic recombination rate of 5.5% was observed in embryos, predominantly in the hotspots (exons 45-55 and exons 3-9) of DMD deletion/duplication mutations. Prenatal diagnosis for 52 families and successful outcomes in all 85 healthy deliveries (live birth rate, 65.89%, 85/129) validated the accuracy and effectiveness of PGT-M. This study provides a highly effective PGT-M strategy (Strategy 5) for DMD/BMD by comparing five different strategies, with the diagnostic yield reaching 99.56%. The results underscore the significance of monitoring intragenic recombination in DMD, which is a frequent occurrence in DMD/BMD.

References
1.
Abbs S, Roberts R, Mathew C, Bentley D, Bobrow M . Accurate assessment of intragenic recombination frequency within the Duchenne muscular dystrophy gene. Genomics. 1990; 7(4):602-6. DOI: 10.1016/0888-7543(90)90205-9. View

2.
Birnkrant D, Bushby K, Bann C, Alman B, Apkon S, Blackwell A . Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management. Lancet Neurol. 2018; 17(4):347-361. PMC: 5889091. DOI: 10.1016/S1474-4422(18)30025-5. View

3.
Capalbo A, Valero R, Jimenez-Almazan J, Mir Pardo P, Fabiani M, Jimenez D . Optimizing clinical exome design and parallel gene-testing for recessive genetic conditions in preconception carrier screening: Translational research genomic data from 14,125 exomes. PLoS Genet. 2019; 15(10):e1008409. PMC: 6797235. DOI: 10.1371/journal.pgen.1008409. View

4.
Capalbo A, Fabiani M, Caroselli S, Poli M, Girardi L, Patassini C . Clinical validity and utility of preconception expanded carrier screening for the management of reproductive genetic risk in IVF and general population. Hum Reprod. 2021; 36(7):2050-2061. DOI: 10.1093/humrep/deab087. View

5.
Chen J, Hejtmancik J, Romeo G, Lindlof M, Boehm C, Caskey C . A genetic linkage map of five marker loci in and around the Duchenne muscular dystrophy locus. Genomics. 1989; 4(1):105-9. DOI: 10.1016/0888-7543(89)90322-4. View