No male segregation distortion of DR2 haplotypes in Japanese narcoleptic patients.
Segregation of narcolepsy-associated DR2/DQw1 haplotypes was studied in 19 informative Japanese families. Each family consisted of a DR2-heterozygous patient, his or her spouse, and their children. In contrast to the previous study on Caucasian narcolepsy, no segregation distortion of the DR2/DQw1 haplotype was observed. The DR2/DQw1 haplotypes were inherited by 9 of 22 offspring from fathers (41%, p = 0.54) and by 10 of 14 offspring from mothers (71%, p = 0.16). These data show that there is no significant segregation distortion of the DR2/DQw1 haplotype in Japanese patients with narcolepsy.