title: MICA gene and ankylosing spondylitis: linkage analysis via a transmembrane-encoded triplet repeat polymorphism.
abstract: In order to address the possibility that the MICA gene located 47 kb upstream from HLA-B is involved in the pathogenesis of ankylosing spondylitis (AS), we have investigated microsatellite polymorphism in the transmembrane region of MICA in Caucasian patients with AS. The microsatellite allele consisting of 4 repetitions of GCT/AGC was present at significantly higher frequency in the patient group (Pc<0.0000001) than in the ethnically matched control group. However, the frequency of the (GCT/AGC)4 allele was significantly low in the B27-positive patients than in the B27-positive healthy controls (Pc=0.0145). These observations suggest that B27 itself remains the primary genetic marker for AS, although the significantly dissimilar phenotype frequency of the (GCT/AGC)4 allele in B27-positive patients and healthy individuals may reflect the existence of other genetic factor(s) in the HLA-B27 haplotype involved in the development of AS.
authors.affiliation: Department of Ophthalmology, Yokohama City University School of Medicine, Kanagawa, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Goto
authors.forename: M
authors.initials: M
authors.lastname: Ota
authors.forename: S
authors.initials: S
authors.lastname: Ohno
authors.forename: N
authors.initials: N
authors.lastname: Mizuki
authors.forename: H
authors.initials: H
authors.lastname: Ando
authors.forename: Y
authors.initials: Y
authors.lastname: Katsuyama
authors.forename: W P
authors.initials: WP
authors.lastname: Maksymowych
authors.forename: M
authors.initials: M
authors.lastname: Kimura
authors.forename: S
authors.initials: S
authors.lastname: Bahram
authors.forename: H
authors.initials: H
authors.lastname: Inoko
mesh_terms: D000483:Alleles; D001483:Base Sequence; D008040:Genetic Linkage; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D013167:Spondylitis, Ankylosing / Q000235:genetics*; D018911:Trinucleotide Repeats / Q000235:genetics*
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A