TY - JOUR T1 - Mendelian segregation of normal CAG trinucleotide repeat alleles at three autosomal loci JF - Journal of Medical Genetics JO - J Med Genet SP - 258 LP - 259 DO - 10.1136/jmg.36.3.258 VL - 36 IS - 3 AU - J C MacMillan AU - J Voisey AU - S C Healey AU - N G Martin Y1 - 1999/03/01 UR - http://jmg.bmj.com/content/36/3/258.abstract N2 - 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. ER -