The association of HLA with young-onset keratoconus in Japan.
OBJECTIVE
To report the association of HLA antigens with keratoconus in Japanese patients.


METHODS
Observational consecutive case series.


METHODS
In 90 consecutive Japanese keratoconus patients, HLA class I (HLA-A, -B, -C) and class II (HLA-DR, -DQ) were analyzed.


RESULTS
Compared with control frequencies, based on mean gene frequencies for the Japanese population, higher frequencies of HLA-A26, B40, and DR9 antigens were found in patients whose conditions were diagnosed before 20 years of age (chi(2) = 6.45, P =.01; chi(2) = 6.78, P =.01; chi(2) =3.99, P =.05, respectively), but were not found in patients whose conditions were diagnosed later in life. Men were significantly younger at diagnosis than were women. No obvious relation was found between HLA antigens and other clinical data.


CONCLUSIONS
HLA-A26, B40, and DR9, which were found relatively frequently in the ancient Japanese population, seem to be associated with keratoconus in younger individuals.
Adachi
Wakako
W
Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kawaramachi, Hirokoji, Kamigyo-ku, Kyoto, Japan. wadachi@ophth.kpu-m.ac.jp
Mitsuishi
Yoko
Y
Terai
Kazuto
K
Nakayama
Chisato
C
Hyakutake
Yoko
Y
Yokoyama
Junko
J
Mochida
Chikako
C
Kinoshita
Shigeru
S
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D002648:Child; D005260:Female; D005787:Gene Frequency; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007640:Keratoconus / Q000208:ethnology / Q000235:genetics*; D008297:Male; D008875:Middle Aged
D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II