P118 Presence of HLA extended haplotypes and KIR association in health and diseases in South India

Abstract

Aim To study the HLA/KIR interactions in health (HC) and disease (DC) (T1DM, T2DM, AITD, CAD, IS, PKF and AKF) cohorts with reference to two extended haplotypes (EHs). Methods Individuals with ‘DRB1∗07-DQB1∗02’ (HC = 168/1353; DC = 271/1376) and ‘DRB1∗15-DQB1∗06’ (HC = 542/1737; DC = 427/1617) haplotypes were typed for HLA-A/B/C by PCR-SSP. Individuals with EHs were KIR genotyped by duplex PCR-SSP. Results Among DRB1∗07-DQB1∗02 individuals, 20.23% (HC, 34/168) and 22.14% (DC, 60/271) possessed the EH ‘A∗03-B∗07-Cw∗07-DRB1∗07-DQB1∗02’. Among DRB1∗15-DQB1∗06 individuals, 9.59% (HC, 52/542) and 19.20% (DC, 82/427) possessed ‘A∗03-B∗07-Cw∗07-DRB1∗15-DQB1∗06’ (AEH 7.1). KIR typing in ‘A∗03-B∗07-Cw∗07-DRB1∗07-DQB1∗02’ (DC, 60; HC, 34) revealed an increased frequency of inhibitory-KIR (iKIR) 2DL3 (susceptible; OR = 59.21; p −5 ) and reduced frequency of 3DL2 (protective; OR = 0.18; p −4 ). Likewise, KIR typing in ‘A∗03-B∗07-Cw∗07-DRB1∗15-DQB1∗06’ (DC, 82; HC, 52), have revealed an increased frequency of iKIR 2DL2 (susceptible; OR = 11.29; p p iso80 were decreased (protective; OR = 0.19; p p iso80 were increased (susceptible; OR = 2.75; p Iso80 were decreased (protective; OR = 0.36; p Conclusions The predominance of the extended haplotypes revealed a selection advantage for these haplotypes in south India. The evolutionary pressure has propensity to maintain HLA-KIR combinations in health and diseases and raises interesting insights and speculations.