CAG repeat lengths in X- and Y-bearing sperm indicate that gender bias during transmission of Huntington's disease gene is determined in the embryo.
The size of the CAG tract at the Huntington's disease (HD) locus upon transmission depends on the gender of the parent. However, the basis for the parent-of-origin effect is unknown. To test whether expansion and contraction in HD are "imprinted" in the germ cells, we isolated the X- and Y-bearing sperm of HD transgenic mice. Here we show that CAG repeat distributions in the X- and Y-bearing spermatozoa of founding fathers do not differ. These data show that gender-dependent changes in CAG repeat length arise in the embryo.
Kovtun
Irina V
IV
Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
Welch
Glenn
G
Guthrie
H David
HD
Hafner
Kari L
KL
McMurray
Cynthia T
CT
D000818:Animals; D004622:Embryo, Mammalian / Q000502:physiology; D006801:Humans; D006816:Huntington Disease / Q000196:embryology / Q000209:etiology / Q000235:genetics*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D012091:Repetitive Sequences, Nucleic Acid; D012737:Sex Factors; D013094:Spermatozoa / Q000502:physiology; D018911:Trinucleotide Repeats; D014960:X Chromosome; D014998:Y Chromosome