title: HLA-DR6 association confers increased resistance to T. rubrum onychomycosis in Mexican Mestizos.
abstract: BACKGROUND
  Onychomycosis is multifactorial in origin. Studies have suggested an autosomal dominant pattern of inheritance and human leukocyte antigen DR4 (HLA-DR4) has been shown to protect against onychomycosis in an Ashkenazi Jewish population.
  
  
  OBJECTIVE
  This study investigates HLA class II association in a Mexican Mestizo population with Trichophyton rubrum onychomycosis.
  
  
  METHODS
  This was a prospective case-control study. Mexican Mestizos with a clinical diagnosis of onychomycosis and culture positive for T. rubrum were recruited, together with age- and sex-matched controls. First-degree relatives were also investigated for onychomycosis. Case-control samples were HLA typed by polymerase chain reaction sequence-specific primer based analysis.
  
  
  RESULTS
  Twenty-one cases and 42 controls were recruited with a mean age of 40 years (range: 18-58 years). HLA-DR6 was found in seven (33%) cases and 19 (45%) controls [P < 0.023, odds ratio (OR) = 0.088, 95% confidence interval (CI): 0.01-0.71]. Six (29%) cases and three (7%) controls had an affected child (P < 0.043, OR = 9.15, 95% CI: 1.07-78.31), and 13 (62%) cases and 12 (29%) controls had an affected first-degree relative (P < 0.02, OR = 4.0, 95% CI: 1.1-14.3).
  
  
  CONCLUSIONS
  These results suggest that HLA-DR6 confers protection against the development of onychomycosis in a Mexican Mestizo population. Having an affected first-degree relative significantly increases the risk of onychomycosis, suggesting genetic susceptibility.
authors.affiliation: Department of Dermatology, Hospital General Dr. Manuel Gea González, Mexico DF, Mexico. dasck@hotmail.com
authors.forename: Daniel
authors.initials: D
authors.lastname: Asz-Sigall
authors.forename: Lirio
authors.initials: L
authors.lastname: López-García
authors.forename: María Elisa
authors.initials: ME
authors.lastname: Vega-Memije
authors.forename: Rosa María
authors.initials: RM
authors.lastname: Lacy-Niebla
authors.forename: Cristina
authors.initials: C
authors.lastname: García-Corona
authors.forename: Claudia
authors.initials: C
authors.lastname: Ramírez-Rentería
authors.forename: Julio
authors.initials: J
authors.lastname: Granados
authors.forename: Antonio
authors.initials: A
authors.lastname: Villa
authors.forename: Mahreen
authors.initials: M
authors.lastname: Ameen
authors.forename: Roberto
authors.initials: R
authors.lastname: Arenas
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D044383:Black People / Q000235:genetics; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D015808:HLA-DR6 Antigen / Q000235:genetics*; D006801:Humans; D007199:Indians, South American / Q000235:genetics; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D014009:Onychomycosis / Q000208:ethnology* / Q000235:genetics* / Q000382:microbiology; D011446:Prospective Studies; D014249:Trichophyton / Q000302:isolation & purification; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: D015808:HLA-DR6 Antigen