Interferon stimulates the expression of a number of genes encoding enzymes with antiviral activities, including myxovirus resistance-1 (MxA), 2-5-oligoadenylate synthetase 1 (OAS-1) and double-stranded RNA-dependent protein kinase (PKR). We examined whether polymorphisms in these genes influenced the outcome of hepatitis C virus (HCV) infection. We observed a lower frequency of the GG genotype at position À88 in the MxA gene promoter in self-limiting HCV infection (OR ¼ 0.56; 95% CI: 0.35-0.8; P ¼ 0.010) and in nonresponders to therapy (OR ¼ 0.49; 95% CI: 0.25-0.95; P ¼ 0.020). This genotype predominantly influenced the outcome of treatment in patients with viral genotype 1 (OR ¼ 0.22 95% CI: 0.07-0.67; P ¼ 0.002). A polymorphism in the 3 0 -untranslated region of the OAS-1 gene was associated with outcome of infection (GG genotype less frequent in self-limiting infection: OR ¼ 0.43; 95% CI: 0.21-0.86; P ¼ 0.010). A polymorphism at position À168 in the promoter region of the PKR gene was associated with self-limiting infection (CT genotype: OR ¼ 2.75; 95% CI: 1.45-5.24; P ¼ 0.002). Further associations were found with a CGG trinucleotide repeat in the 5 0 UTR region of the PKR gene. Polymorphisms in the interferon-induced genes, MxA, OAS-1 and PKR appear thus associated with HCV outcome.

Abbreviations: HCV, hepatitis C virus; HLA, human leukocyte antigen; IFN, interferon; KIR, MHC, major histocompatability complex; SVR, sustained virological response. From the

The natural outcome and response to treatment in hepatitis C virus (HCV) infection varies between individuals. Whereas some variation may be attributable to viral and environmental variables, it is probable that host genetic background also plays a significant role. Interleukin (IL)-10 has a key function in the regulation of cellular immune responses and in the suppression of pro-inflammatory cytokine secretion. Functional polymorphisms in the IL-10 gene have been described. We investigated the role of these polymorphisms in the outcome of HCV infection, treatment response and development of fibrosis in a case-control association study. Self-limiting infection was associated with the IL-10 (-592) AA genotype (OR=2.05; P=0.028). Persistent infection was associated with the IL-10 (-1082) GG genotype (OR=0.48; P=0.018). Sustained response to interferon therapy was associated with the IL-10 (-1082) GG genotype (OR=2.28; P=0.005) and the haplotype GCC (OR=2.27; P=0.020). The IL-10 (-1082) AA genotype and the ATA/ATA and ACC/ACC homozygous haplotypes were more frequent among patients with rapid fibrosis. Furthermore, the microsatellites IL-10.R and IL-10.G were associated with interferon response with IL-10R.2 conveying susceptibility (OR=1.80; P=0.034), and IL-10R.3 and IL-10.G13 being protective (OR=0.47; P=0.003 and OR=0.59; P=0.042, respectively). We conclude that polymorphisms in the IL-10 promoter appear to have some influence on the outcome of HCV infection, treatment and development of fibrosis.

In striking contrast to adults, in children sleep following training a motor task did not induce the expected (offline) gain in motor skill performance in previous studies. Children normally perform at distinctly lower levels than adults. Moreover, evidence in adults suggests that sleep dependent offline gains in skill essentially depend on the pre-sleep level of performance. Against this background, we asked whether improving children's performance on a motor sequence learning task by extended training to levels approaching those of adults would enable sleep-associated gains in motor skill in this age group also. Children (4-6 years) and adults (18-35 years) performed on the motor sequence learning task (button-box task) before and after ~2-hour retention intervals including either sleep (midday nap) or wakefulness. Whereas one group of children and adults, respectively, received the standard amount of 10 blocks of training before retention intervals of sleep or wakefulness, a further group of children received an extended training on 30 blocks (distributed across 3 days). A further group of adults received a restricted training on only two blocks before the retention intervals. Children after standard training reached lowest performance levels, whereas in adults performance after standard training was highest. Children with extended training and adults after reduced training reached intermediate performance levels. Only at these intermediate performance levels did sleep induce significant gains in motor sequence skill, whereas performance did not benefit from sleep in the low-performing children or in the high-performing adults. Spindle counts in the post-training nap were correlated with performance gains at retrieval only in the adults benefitting from sleep. We conclude that, across age groups, sleep induces the most robust gain in motor skill at an intermediate pre-sleep performance level. In low-performing children sleep-dependent improvements in skill may be revealed only after enhancing the pre-sleep performance level by extended training.

Persistent hepatitis B virus infection is a major risk factor for hepatocellular carcinoma, the most frequent cancer in some developing countries. Up to 95% of those infected at birth and 15% of those infected after the neonatal period fail to clear hepatitis B virus, together resulting in Ϸ350 million persistent carriers worldwide. Via a whole genome scan in Gambian families, we have identified a major susceptibility locus as a cluster of class II cytokine receptor genes on chromosome 21q22. Coding changes in two of these genes, the type I IFN receptor gene, IFN-AR2, and the IL-10RB gene that encodes a receptor chain for IL-10-related cytokines including the IFN-s, are associated with viral clearance (haplotype P value ‫؍‬ 0.0003), and in vitro assays support functional roles for these variants in receptor signaling.complex trait ͉ IL-10 ͉ interferon ͉ susceptibility ͉ virus T here are Ϸ350 million people with persistent hepatitis B virus (HBV) infection worldwide. Of these infected people, up to one-quarter will die from complications of the infection including cirrhosis and primary liver cancer. However, infection with HBV does not invariably lead to chronic hepatitis: When infection is acquired during childhood, as is normally the case in subSaharan Africa, up to 90% will eliminate the virus spontaneously. When infection is acquired during the early neonatal period from an HBV-infected mother, only 10% of children will eliminate the virus, but this situation, known as vertical transmission, is rare in Africa.Susceptibility to persistent infection is governed by a number of factors, in addition to the age at infection. Twin studies and limited genetic association study data indicate that host genetic background influences the outcome of infection (1). It is likely that genetic susceptibility to persistent HBV infection is polygenic, and that both MHC and non-MHC genes are involved (2).Current treatment for persistent HBV infection is partially effective, expensive, and impractical in developing countries where persistent HBV infection rates are at their highest (3). It is therefore crucial to identify factors that determine whether HBV becomes a self-limiting or persistent infection because these factors may reveal new therapeutic opportunities for patients with chronic HBV infection. This study was conducted to identify genetic determinants of persistent HBV infection by using a genomewide approach. ResultsTo search for major loci that might have some effect on viral persistence in a highly endemic area, 318 microsatellites were analyzed in 88 independent affected sibling pairs (ASPs) in 61 Gambian families. The most significant evidence of linkage was found on chromosome 21 [logarithm of odds (lod) ϭ 1.66; P ϭ 0.003] (Table 1, which is published as supporting information on the PNAS web site). This locus on chromosome 21 also showed evidence of linkage when a total of 31 markers (with SIBPAIR P value Ͻ0.1) were followed up in a further 106 independent ASPs in 74 families (D21S1252 screens 1 and 2 combined: ...

The presence of ovarian cancer, or factors known to increase risk for the disease, i.e. age or BRCA1 germline mutations, are significantly associated with a dominant community-type O cervico-vaginal microbiota. Whether re-instatement of communitytype L microbiome, using, for instance, vaginal suppositories containing live lactobacilli, would indeed alter the microbiomial load and composition higher up in the female genital tract, and at the Fallopian Tube, the site of origin of high grade serous ovarian cancer, and whether this would translate into a reduced rate of ovarian cancer, needs to be determined.

Background & AimsPolymorphisms in the interleukin-28B (IL28B) gene are associated with outcomes from infection with hepatitis C virus (HCV). However, the role of these polymorphisms in protecting injection drug users who are at high risk for HCV infection but do not have detectable antibodies against HCV or HCV RNA (exposed uninfected) has not been demonstrated. We investigated whether these individuals have the IL28B genotype rs12979860-CC, which protects some individuals against HCV infection.MethodsSeventy-four exposed uninfected individuals, 89 spontaneous resolvers, and 234 chronically infected individuals were genotyped to determine single nucleotide polymorphisms at IL28B.rs12979860.ResultsExposed, uninfected individuals had a significantly lower frequency of the protective genotype (rs12979860-CC) than anti-HCV-positive spontaneous resolvers (41.9% vs 69.7%, respectively; P = .0005; odds ratio [OR], 0.31; 95% confidence interval [CI]: 0.16–0.60) but a similar frequency to patients who were chronically infected (41.9% vs 43.6%, respectively; P = ns). However, exposed, uninfected individuals had a significantly higher frequency of homozygosity for killer cell immunoglobulin-like receptor 2DL3:group 1 HLA-C (KIR2DL3:HLA-C1) than those with chronic infection (31.1% vs 13.3%, respectively; P = .0008; OR, 2.95; 95% CI: 1.59–5.49). For patients who spontaneously resolved infection, IL28B and KIR:HLA protected, independently, against chronic HCV infection, based on logistic regression and synergy analyses (synergy factor, 1.3; 95% CI: 0.37–4.75; P synergy = .6).ConclusionsIL28B and KIR2DL3:HLA-C1 are independently associated with spontaneous resolution of viremia following HCV exposure. Resistance to HCV infection in exposed uninfected cases is associated with homozygosity for KIR2DL3:HLA-C1 but not the single nucleotide polymorphism IL28B.rs12979860. Uninfected individuals are therefore a distinct population from patients who spontaneously resolve HCV infection. Distinct, nonsynergistic innate immune mechanisms can determine outcomes of HCV exposure.

No abstract