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The increasing relevance of human Y-STRs in forensic science demands reliable estimates of their mutation rates. Therefore, a collaborative study was carried out by the Spanish and Portuguese working group of the International Society for Forensic Genetics (GHEP-ISFG) in the interest of extending the data on Y-chromosomal short tandem repeat (Y-STR) mutation rates. Sixteen Y-STRs were considered in the analyses: DYS456, DYS389I, DYS389II, DYS390, DYS458, DYS19, DYS385, DYS391, DYS392, DYS393, DYS439, DYS635, DYS437, DYS438, DYS448, GATA H4. Among the sample of 1598 father-son duos analyzed, 46 mutations were observed, 45 of which were a single-step change and 1 was a double-step change. A total of 28 repeat losses were observed against 18 gains, with a ratio of 1:1.5. Eleven duos showing double alleles at the Y-STR loci DYS19, DYS391, DYS439 and DYS448 without allelic discrepancy between the father-son duo were also observed. This new data was added to the previous studies from the GHEP-ISFG working group, totalizing 63 496 allele transmissions (varying between 2298 and 7347 per locus). The average mutation rate across all 16 Y-STRs loci was 0.00187 (95% CI 0.00155–0.00224). The average mutation rates per marker varied between 0.00057 (95% CI 0.00007–0.00206) at DYS438 and 0.00606 (95% CI 0.00375–0.00925) at DYS439.

We investigated the effect of the -278A>C polymorphism in the CYP7A1 gene on the response of plasma lipids to a reduced-fat diet for 6 to 8 weeks in a group of 82 dyslipidemic males with a mean age of 46.0 ± 11.7 years. Individuals who presented at least one high alteration in total cholesterol, low-density lipoprotein cholesterol or triglyceride values were considered to be dyslipidemic. Exclusion criteria were secondary dyslipidemia due to diabetes mellitus, renal, liver, or thyroid disease. None of the subjects were using lipid-lowering medication. Baseline and follow-up lipid concentrations were measured. The genotypes were determined by the digestion of PCR products with the BsaI restriction endonuclease. There were statistically significant reductions in plasma total cholesterol, low-density lipoprotein cholesterol and triglyceride concentrations after dietary intervention. The minor allele C has a frequency of 43%. Carriers of the C allele had significantly lower triglyceride concentrations (P = 0.02) than AA homozygotes. After adjustment of covariates, subjects with the AC and CC genotypes showed a greater reduction in triglyceride concentrations compared to subjects with the AA genotype. Multiple linear regression analyses showed that the AC and CC CYP7A1 genotypes accounted for 5.2 and 6.2% of triglyceride concentration during follow-up and adjusted percent of change of triglyceride concentration, respectively. The present study provides evidence that -278A>C polymorphism in the CYP7A1 gene can modify triglyceride concentrations in response to a reduced fat diet in a dyslipidemic male population. This gene represents a potential locus for a nutrigenetic directed approach.

Objective The aim of this study was to determine the rate of occult hepatitis B virus (HBV) infection among blood donors living in a geographic region of low (5.6%) anti-HBc prevalence. Subjects and methods Sera from 150 candidate blood donors whose blood was rejected due to total anti-HBc reactivity (despite absence of HBsAg) were tested for anti-HBs and IgM anti-HBc antibodies, as well as for HBeAg/anti-HBe. Serum HBV DNA was sought by using a PCR assay able to amplify part of the surface gene. Viral load was measured in the PCR positive samples. Results The pattern 'anti-HBc alone' (without HBsAg and anti-HBs antibodies) was found in 64 (42.7%) subjects. IgM anti-HBc and anti-HBe antibodies were detected in 2 (1.3%) and 80 (53.3%) samples, respectively. No sample was HBeAg-reactive. HBV DNA was repeatedly found in five (3.3%) samples, three of which were anti-HBs positive and two anti-HBs negative. All five HBV DNA positive samples showed a low viral load ( Conclusions The data indicated a low rate of occult infection among anti-HBc positive, HBsAg negative blood donors living in a region of low prevalence of infection. Viral load was very low in all HBV infected subjects.