Mendelian segregation of normal CAG trinucleotide repeat alleles at three autosomal loci.
Segregation ratio distortion (SRD) with preferential transmission of expanded CAG alleles has been reported in Machado-Joseph disease (MJD/SCA3), spinocerebellar ataxia type I (SCA1), and dentatorubral-pallidoluysian atrophy (DRPLA). We have examined the transmission frequencies of alleles in normal heterozygotes at these disease loci in 377 pairs of twins and their parents and find no evidence for SRD.
MacMillan
J C
JC
Department of Medicine, University of Queensland Graduate School of Medicine, and Queensland Institute of Medical Research, Herston, Brisbane, Australia.
Voisey
J
J
Healey
S C
SC
Martin
N G
NG
D000293:Adolescent; D000328:Adult; D000483:Alleles; D020090:Chromosome Segregation; D006801:Humans; D017827:Machado-Joseph Disease / Q000235:genetics*; D019636:Neurodegenerative Diseases / Q000235:genetics*; D013132:Spinocerebellar Degenerations / Q000235:genetics*; D018911:Trinucleotide Repeats; D014427:Twins