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Background: Human leukocyte antigen (HLA) complex is a gene family involved in antigen presentation associated with protection or susceptibility to inflammatory, infectious and autoimmune diseases. Atherosclerosis is a chronic inflammatory disease in which HLA molecules play a role in the initiation and development of the disease through presentation of self or foreign antigens to T cells. Objective: To investigate the association of HLA-DRB1 alleles with atherosclerosis in a sample of southwestern Iranians. Methods: We performed an analytical cross-sectional study involving 96 patients with atherosclerosis and 72 controls. HLA-DRB1 genotyping was performed by PCR-SSP method. Results: We observed a significantly lower frequency of DRB1*01 in patients with coronary artery atherosclerosis than in controls (4.68% vs. 13.1, P=0.0052, OR=3.09, CI 95%: 1.35-7.05). However, this allele showed a positive association with high blood pressure (P=0.009) in patients. Furthermore, DRB1*16 allele was associated with hyperlipidemia (P=0.008) in patients. Conclusion: Our results demonstrated that DRB1*01 may be a protective allele against atherosclerosis in individuals who live in southwest of Iran. The mechanism of this protection needs further investigation.

Background/Aims: Present-day Iran has long represented a natural hub for the expansion of human genes and cultures. That being so, the overlapping of prehistoric and more recent demographic events interacting at different time scales with geographical and cultural barriers has yielded a tangled patchwork of anthropological types within this narrow area. This study aims to comprehensively evaluate this ethnic mosaic by depicting a fine-grained picture of the Iranian mitochondrial landscape. Methods: mtDNA variability at both HVS-I and coding regions was surveyed in 718 unrelated individuals belonging to 14 Iranian ethnic groups characterized by different languages, religions and patterns of subsistence. Results: A discordant pattern of high ethno-linguistic and low mtDNA heterogeneity was observed for the whole examined Iranian sample. Geographical factors and cultural/linguistic differences actually represented barriers to matrilineal gene flow only for the Baloch, Lur from Yasouj, Zoroastrian and Jewish groups, for which unusual reduced levels of mtDNA variability and high inter-population distances were found. Conclusion: Deep rooting genealogies and endogamy in a few of the examined ethnic groups might have preserved ancestral lineages that can be representative of Proto-Indo-Iranian or prehistoric mitochondrial profiles which survived relatively recent external contributions to the Iranian gene pool.

Contains fulltext : 108117.pdf (Publisher’s version ) (Closed access) Infectious diseases exert a constant evolutionary pressure on the innate immunity genes. TLR4, an important member of the TLR family, specifically recognizes conserved structures of various infectious pathogens. Two functional TLR4 polymorphisms, Asp299Gly and Thr399Ile, modulate innate host defense against infections, and their prevalence between various populations has been proposed to be influenced by local infectious pressures. If this assumption is true, strong local infectious pressures would lead to a homogeneous pattern of these ancient TLR4 polymorphisms in geographically-close populations, while a weak selection or genetic drift may result in a diverse pattern. We evaluated TLR4 polymorphisms in 15 ethnic groups in Iran, to assess whether infections exerted selective pressures on different haplotypes containing these variants. The Iranian subpopulations displayed a heterogeneous pattern of TLR4 polymorphisms, comprising various percentages of Asp299Gly and Thr399Ile, alone or in combination. The Iranian sample, as a whole, showed an intermediate mixed pattern when compared with commonly-found patterns in Africa, Europe, Eastern Asia and the Americas. These findings suggest a weak, or absent, selection pressure on TLR4 polymorphisms in the Middle-East that does not support the assumption of an important role of these polymorphisms in the host defense against local pathogens. 01 juni 2012