DRB1* 140103 (P= 0.024, OR: 13.526, 95% CI: 1.381 to 132.49), and HLA-DQB1* 050201 (P< 0.0001, OR: 28.556, 95% CI: 8.36 to 242.16) and a significantly decreased frequency was observed in HLA-B5 (P= 0.009, OR: 0.434, 95% CI: 0.236 to 0.799), HLADQB1* 030101 (P= 0.045, OR: 0.219, 95% CI: 0.051 to 0.940), HLADQB1* 060101 (P= 0.012, OR: 0.334, 95% CI: 0.145 to 0.770), alleles in HIV+/PTB+ coinfected patients when compared with healthy controls. Significantly increased frequency of HLA-A10 (P= 0.086, OR: 0.502, 95% CI: 0.24 to 1.03), was observed in HIV+/PTB+ coinfected patients when compared with HIV+ PTBÀ patients. We have studied, HLA-A, B, DRB, and DQB loci to find out the role of these HLA alleles in HIV+/PTB+ coinfection. Significantly increased frequency of HLA-B8 and HLA-DQB* 030103 in HIV+/PTB+ coinfected patients against controls may suggest that these alleles play an associative role in HIV infection and PTB development. But on the contrary, a significantly decreased frequency of HLA-B8 and HLA-DQB* 030103 observed in HIV+/PTB+ coinfected patients when compared with HIV+ PTBÀ patients may be suggestive of their protective role in PTB development. Our study reveals that HLA-B8 and HLA-DQB* 030103 are associative to enhance HIV infection but play a protective role in development of PTB coinfection. The decreased frequency of HLA-DQB1* 0301 has been reported in PTB patients from China. 6 In our study, HLA-DQB1* 030101 is decreased in HIV+/PTB+ coinfected patients compared with controls suggesting that it may play a protective role in HIV+/PTB+ coinfection, whereas HLA-DQB* 030103 is associative in HIV infection but plays a protective role in development of PTB in HIV infected patients. Recently among south Indians, an increased frequency of HLA-DQB1* 0601 has been reported in HIVÀ PTB+ and HIV+ PTB+ patients, suggesting that HLA-DQB1* 0601 is associated with susceptibility to PTB as well as development of PTB in HIV patients. 7 Further earlier association of HLA-DQB1* 0601 with susceptibility to PTB has also been reported in south India. 8 In contrast to the

640| www. jaids. com J Acquir Immune Defic Syndr Volume 51, Number 5, August 15, 2009 above 2 studies on south Indian population, it is reported that HLA-DQB1* 0601 plays a protective role against HIV disease progression in Europeans. 9 In our study, a significantly increased frequency of HLA-DQB* 060102 in HIV+/PTB+ coinfected patients when compared with controls and HIV+ PTBÀ patients may suggest its strong association with both HIV infection and PTB coinfection. But on the contrary, HLA-DRB1* 060101 frequency was significantly decreased in HIV+/PTB+ coinfected patients compared with controls, thereby may protect from HIV infection and PTB development. HLA-DQB1* 0502 allele is reportedly related to high risk of developing TB in population from Asia and Latin America. 10 In the present study, frequency of HLA-DQB1* 050201 is increased in HIV+/PTB+ coinfected patients compared with healthy subjects to show that HLADQB1* 050201 may be associated with HIV+/PTB+ coinfection. There was no considerable change in frequency of HLA-A10 in HIV+/PTB+ coinfected patients when compared with controls and also decreased frequency was observed when compared with HIV+ PTBÀ patients. This suggests that HLA-A10 may not be associated with HIV infection and also may play a protective role in PTB development. HLA-A31 and HLA-B41 antigens and the HLA-DRB1* 10 and HLA-DQB1* 05 were overrepresented in Brazilian patients with AIDS and tuberculosis (TB), suggesting association to …