Further evidence of the role of HLA-DR4 in the genetic susceptibility to actinic prurigo.
BACKGROUND
Actinic prurigo (AP) is triggered by sun exposure. Its prevalence in Mexicans seems to be particularly high, which suggests a genetic susceptibility.


OBJECTIVE
Our purpose was to determine the role of major histocompatibility complex (MHC) genes in the genetic susceptibility to AP.


METHODS
Fifty-six Mexican Mestizo patients with AP underwent serologic typing for HLA class I and class II antigens. Class II MHC genes were also studied by DNA analysis. Findings in patients were compared with 100 ethnically matched healthy controls.


RESULTS
We found that 92.8% of patients with AP were HLA-DR4 positive (corrected p = 0.002; odds ratio [OR] = 10.1). The class I antigens HLA-A28 and HLA-B39 (B16) were also significantly increased (p < or = 0.000001, OR = 20.9 and p = 0.0001, OR = 6.7, respectively) compared with normal controls. Allele-specific oligonucleotide DR4 subtyping showed that 80.7% of HLA-DR4+ patients with AP were also positive for the DRB1*0407 allele.


CONCLUSIONS
These results confirm the role of HLA-DR4 (DRB1*0407) in the genetic susceptibility to AP and raise the possibility of a role for class I MHC antigens HLA-A28 and B16 in Mexican patients.
Hojyo-Tomoka
T
T
Department of Dermatology, Hospital General Dr. Manuel Gea González, Tlalpan D.F., Mexico.
Granados
J
J
Vargas-Alarcón
G
G
Yamamoto-Furusho
J K
JK
Vega-Memije
E
E
Cortés-Franco
R
R
Flores
O
O
Teixeira
F
F
Domínguez-Soto
L
L
D000293:Adolescent; D000328:Adult; D002648:Child; D004198:Disease Susceptibility; D005006:Ethnicity; D005260:Female; D015235:HLA-B Antigens / Q000032:analysis; D006684:HLA-DR Antigens / Q000032:analysis*; D015395:Histocompatibility Antigens Class I / Q000032:analysis; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D006801:Humans; D007198:Indians, North American / Q000235:genetics; D008297:Male; D008800:Mexico; D008875:Middle Aged; D010641:Phenotype; D011536:Prurigo / Q000208:ethnology / Q000209:etiology* / Q000235:genetics* / Q000276:immunology; D013472:Sunlight / Q000009:adverse effects*; D044465:White People / Q000235:genetics
D015235:HLA-B Antigens; D006684:HLA-DR Antigens; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II