Objective: The contribution of polymorphism of transporter associated
with antigen processing 1 and 2 (TAP1 and 2) alleles to the pathogenes
is of Japanese SSc was studied. Methods: TAP1 and TAP2 typing was carr
ied out in 55 Japanese SSc patients and 95 normal Japanese subjects by
the PCR-RFLP (restriction fragment length polymorphism) method. HLA-D
R typing and HLA DRB115, *16 and *08 genotyping were carried out by t
he PCR and the PCR-SSCP (single-stranded DNA conformation polymorphism
)methods, respectively. Results: The frequencies of the TAP1A and TAP2
A alleles were significantly increased in SSc with diffuse scleroderma
(100%, p < 0.005; 80.0%, p < 0.001, respectively) and in SSc with ant
itopoisomerase 1 antibody (a-Scl-70), (93.2%, p = not significant (NS)
; 63.6%, p < 0.05), In contrast, the TAP1B allele was significantly de
creased in diffuse scleroderma (0%, p < 0.005) and SSc with a-Scl-70 (
4.5%, p < 0.05), and TAP2B was decreased in diffuse scleroderma (12.5%
, p < 0.01). Conclusion: Association analysis among TAP1A, TAP2A and D
RB11502 indicated that increases in TAP1A and TAP2A were not primary,
but were reflective of an increase in HLA DRBI1502 in Japanese SSc p
atients with diffuse scleroderma and SSc with a-Scl-70.