Parental age effects, but no evidence for an intrauterine effect in the transmission of myotonic dystrophy type 1.

ABSTRACT: Myotonic dystrophy type 1 (DM1) is caused by the expansion of an unstable CTG repeat (g.17294_17296(45_1000)) with more repeats associated with increased disease severity and reduced age at onset. Expanded disease-associated alleles are highly unstable in both the germline and soma. Germline instability is expansion biased, providing a molecular explanation for anticipation. Somatic instability is expansion biased, size- and age-dependent, features that have compromised genotype-phenotype correlations and intergenerational studies. We corrected these confounding factors by estimating the progenitor allele length in 54 father-offspring and 52 mother-offspring pairs in Costa Rican DM1 families. Not surprisingly, we found major parental allele length effects on the size of the allele transmit

SUBMITTER: Morales F 

PROVIDER: S-EPMC4402617 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature