Genetic mapping of X-linked loci involved in skewing of X chromosome inactivation in the human.
We have analyzed X-chromosome inactivation patterns in lymphocytes of 264 females from 38 families not known to have any genetic disease. Quantitative measures of X-inactivation showed strong sister-sister correlation in the degree of departure from equal numbers of cells having each X chromosome active, suggesting heritability of this phenotype. Strong sister-sister correlation was also observed for the fraction of cells having the same parent's X chromosome active, consistent with the possibility that this trait might be controlled by a cis-acting, X-linked gene. We used a sib-pair approach to determine whether X-inactivation phenotype was linked to loci in any region of the X chromosome. Both quantitative and discrete measures of X-inactivation phenotype showed evidence of linkage to markers in the region of the X inactivation center (XIC). The quantitative measure of X-inactivation phenotype used in our study also showed linkage to loci at Xq25-q26. This study provides the first evidence for X-linked inheritance of X chromosome inactivation phenotype derived from linkage analysis in phenotypically normal human families.
Naumova
A K
AK
Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia 19140, USA.
Olien
L
L
Bird
L M
LM
Smith
M
M
Verner
A E
AE
Leppert
M
M
Morgan
K
K
Sapienza
C
C
D001483:Base Sequence; D002874:Chromosome Mapping; D017931:DNA Primers; D004303:Dosage Compensation, Genetic; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D009035:Mothers; D009679:Nuclear Family; D010375:Pedigree; D019655:Quantitative Trait, Heritable; D014960:X Chromosome
D017931:DNA Primers