Parental origin and germline mosaicism of deletions and duplications of the dystrophin gene: a European study

✍ Scribed by Anthonie J. Essen; Stephen Abbs; Montserrat Baiget; Egbert Bakker; Catherine Boileau; Christine Broeckhoven; Kate Bushby; Angus Clarke; Mireille Claustres; Angela E. Covone; Maurizio Ferrari; Alessandra Ferlini; Giuliana Galluzzi; Tiemo Grimm; Caroline Grubben; Marc Jeanpierre; Helena Kääriäinen; Sabina Liechti-Gallati; Marie A. Melis; Gert-J. B. Ommen; Jaques E. Poncin; Hans Scheffer; Marianne Schwartz; Astrid Speer; Manfred Stuhrmann; Christine Verellen-Dumoulin; Douglas E. Wilcox; Leo P. Kate

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 903 KB
• Volume: 88
• Category: Article
• ISSN: 0340-6717
• DOI: 10.1007/bf00197255

✦ Synopsis

Knowledge about the parental origin of new mutations and the occurrence of germline mosaicism is important for estimating recurrence risks in Duchenne (DMD) and Becker muscular dystrophy (BMD). However, there are problems in resolving these issues partly because not all mutations can as yet be directly detected, and additionally because genetic ratios are very sensitive to ascertainment bias. In the present study, therefore, analysis was restricted to currently detectable mutations (deletions and duplications) in particular types of families which tend to be rare. In order to obtain sufficient data we pooled results from 25 European centers. In Offprint requests to: A. J. vanEssen mothers of affected patients who were the first in their family with a dystrophin gene deletion or duplication, the ratio between the paternal and the maternal origin of this new mutation was 32:49 (binomial test P = 0.075) for DMD. In five BMD families the ratio between paternal and maternal origin of new mutations was 3:2. Recurrence risk because of maternal germline mosaicism was studied in sisters or subsequent sibs of isolated cases with an apparently new detectable mutation. In 12 out of 59 (0.20; 95%CI 0.10-0.31) transmissions of the risk haplotype the DMD mutation was transmitted as well. No recurrences were found in nine BMD families.