Analysis of dinucleotide repeat loci of dystrophin gene for carrier detection, germline mosaicism and de novo mutations in Duchenne muscular dystrophy

Molecular diagnosis of dystrophinopathies using a multi‐technique analysis algorithm

“…The presence of a deletion at any STR locus increases the certainty of the analysis to 100% . Another molecular event that could affect the certainty of the diagnosis is the occurrence of germline mosacism in patients' parents (15–20%) …”

Prenatal diagnosis of duchenne/becker muscular dystrophy by short tandem repeat segregation analysis in argentine families

“…The identification of de novo mutations is highly significant, as this information allows for exclusion of the disease risk in male offspring and of a carriership in all female relatives of these families. It is also important to evaluate the risk of germline mosaicism in the mother (15–20%) 23, 25…”

“…It is also important to evaluate the risk for germline mosaicism in the patient's parents (frequency ∽15%) 22, 23. This is the case for either a mother with only one affected child (sporadic DMD) or with more than one affected son with no previous history of DMD/BMD in the family.…”

A Larger Spectrum of Intragenic Short Tandem Repeats Improves Linkage Analysis and Localization of Intragenic Recombination Detection in the Dystrophin Gene

“…In pedigree FD# 73, the DXS1242 marker is not informative, but two independent recombinations were mapped ( Figure 3A) subsequent to segregation of the DXS1243, 5Ј-5n3 and 5Ј-5n4 marker alleles, which are not included in the STR panels reported by other groups. 11,19,20 A similar picture is depicted for the recombination event mapped at the 3Ј region of the gene between the DXS1214 and DXS992 markers in pedigree FD# 8 (Figure 3B). Although subject II:2 carried the maternal not-at-risk haplotype from the DXS1242 to the DXS1214 markers, the identification of the recombination between DXS1214 and DXS992 precluded a conclusive diagnosis about the carrier/noncarrier status of subject II:2 because this region could contain a mutation.…”

“…In fact, the use of several STRs in the 5Ј region of the gene (from DXS1242 to DMDSTR07A) allowed us to identify six recombination events that could be missed in case of lack of informativeness of the DXS1242 marker using smaller STR panels, which include only few markers, as reported by others. 11,19,20 Furthermore, the use of several STRs with high heterozygosity in the 3Ј region (from intron 50) of the dystrophin gene enabled us to identify about 24% of all the recombinations found in our population. In contrast, a low number of recombinants (4 to 15% of total recombinants) was identified in this region in other populations, 13,14 probably because of the typing of a smaller STR panel.…”