title: Comparative study of the residues 63 and 67 on the HLA-B molecule in patients with Takayasu's Arteritis.
abstract: Takayasu's Arteritis (TA) has been associated with the Major Histocompatibility Complex (MHC) genes; nevertheless, results in several populations have been heterogeneous. Studies both in Mexican and Asian populations suggest that residues at positions 63 (glutamic acid) and 67 (serine) of the HLA-B molecule could be the genetic markers for TA. In the present work, we analyzed the sequence of HLA-B alleles in 26 TA patients and 62 healthy controls. HLA-B subtyping analysis showed that all B52 alleles were B*5201, whereas only one HLA-B39 allele was B*3902. Sequencing of HLA-B alleles showed that 19 out of 26 patients studied (73.0%) presented at least an allele with glutamic acid at position 63 and serine at position 67. This condition was observed in only 21.0% of the healthy controls (pC = 0.00001, OR = 10.23). Out of the seven remaining patients, one presented glutamic acid at position 63 and four showed serine at position 67. Two patients (2/26 = 7.7%) and 24 healthy controls (24/62 = 38.7%) did not show similarity at the mentioned positions (pC = 0.016, OR = 0.13). These data corroborate the participation of positions 63 and 67 in the genetic susceptibility to TA and explain the high heterogeneity of alleles associated with the disease in several populations.
authors.affiliation: Department of Physiology, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano 1, Col. Sección XVI, Tlalpan 14080, Mexico. gvargas63@yahoo.com
authors.forename: Gilberto
authors.initials: G
authors.lastname: Vargas-Alarcón
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Hernández-Pacheco
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Soto
authors.forename: Luis Enrique
authors.initials: LE
authors.lastname: Murguía
authors.forename: Nonanzit
authors.initials: N
authors.lastname: Pérez-Hernández
authors.forename: Julio
authors.initials: J
authors.lastname: Granados
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Reyes
mesh_terms: D000483:Alleles; D019943:Amino Acid Substitution / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D018698:Glutamic Acid / Q000235:genetics; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D008297:Male; D008800:Mexico; D012694:Serine / Q000235:genetics; D013625:Takayasu Arteritis / Q000175:diagnosis / Q000235:genetics*
chemical_list: D005819:Genetic Markers; D015235:HLA-B Antigens; D018698:Glutamic Acid; D012694:Serine