Clinal patterns of human Y chromosomal diversity in continental Italy and Greece are dominated by drift and founder effects.

We explored the spatial distribution of human Y chromosomal diversity on a microgeographic scale, by typing 30 population samples from closely spaced locations in Italy and Greece for 9 haplogroups and their internal microsatellite variation. We confirm a significant difference in the composition of the Y chromosomal gene pools of the two countries. However, within each country, heterogeneity is not organized along the lines of clinal variation deduced from studies on larger spatial scales. Microsatellite data indicate that local increases of haplogroup frequencies can be often explained by a limited number of founders. We conclude that local founder or drift effects are the main determinants in shaping the microgeographic Y chromosomal diversity.

HLA class II favors clearance of HCV infection and progression of the chronic liver damage.

BACKGROUND/AIMS: This study was aimed to determine whether host-dependent genetic factors modulate the outcome of HCV infection. METHODS: HLA class II DRB and DQB typing was performed in 184 infected patients and 200 healthy volunteers. Among the patients, 149 subjects had persistent HCV viremia (Group 1) and 35 subjects underwent spontaneous viral clearance (Group 2). Group 1 included cirrhotic patients with transfusion-acquired infections (n = 79), asymptomatic HCV carriers (n = 42), and patients with chronic hepatitis C responsive to interferon therapy (n = 28). RESULTS: Spontaneous viral clearance was associated with HLA DRB1*1104 (pc = 0.054, OR = 4.51, 95% C.I. 2.02-10.1) and HLA DQB1*0301 (pc = 0.0039, OR = 4.52, 95% C.I. 2.15-9.51). In Group 1 the haplotype DRB1*1104/DQB1*0301 was less frequent (4.8%) than in Group 2 (18.3%) (pc = 0.009, OR = 7.38, 95% C.I. 2.58-21.59). At the HLA level, cirrhotic patients were not different from asymptomatic HCV carriers and patients with interferon-induced viral clearance. In cirrhotic patients infected with genotype 1b, the DQB1*0502 allele was more frequently found in those with rapidly progressive liver damage (OR = 8.15, 95% C.I. 1.49-44.44), but the corrected p-value was not significant (pc = 0.09). CONCLUSIONS: The HLA haplotype DRB1*1104/DQB1*0301 appears to contribute to the spontaneous clearance of HCV infection. The predominance of the DQB1*0502 allele in cirrhotic patients with a rapidly progressive disease possibly reflects an influence of this allele on the progression of the HCV-related liver disease.