RESUMO
BACKGROUND: There are many well-established factors that influence the risk of stroke including blood pressure, diabetes, low socioeconomic status and smoking, however, the shared genetic resource in members of a family effect on stroke predisposition. Genome-wide association studies (GWAS) have demonstrated evidence of a shared genetic source in stroke risk. This review considered the influence of family history as one of the main risk factors in stroke according to the literature. METHODS: Literature review was obtained by searching for the key words "stroke", "family history" and "stroke gene" in PubMed. An overview has been made on the topics: relevance of stroke family history, family history assessment tools and specific candidate genes for stroke. RESULTS: Family history of stroke is an important risk factor for the development of cerebrovascular diseases in addition to stroke subtypes in relatives who have reached the questionnaire and pedigree. While variation in a small number of loci showed Mendelian inheritance of stroke phenotypes, the genetic variations in several stroke risk loci are shared with multiple related vascular traits. CONCLUSION: This study highlighted the importance of family history in stroke phenotypes and current related genetics information. Increasing awareness of the importance of family history in stroke has the advantage of preventing exposure to stroke with health care.
RESUMO
Chronic hepatitis B virus (HBV) infection increases the risk of developing cirrhosis and hepatocellular carcinoma (HCC) with suspected interactions between virus replication and host immune responses. A number of reports have suggested that telomerase function may be involved in chronic hepatitis B (CHB) pathogenesis, but positive or negative associations with HCC risk remain for discussion. Mean telomere length is an indicator of biological aging and it has been reported that reduction in NBV carriers compared to normal individuals. In somatic cells, telomeres contain simple, tandemly repeated G-rich sequences that frequently are reduced by 50 to 200 base pairs at each cell division. Several genome-wide association studies (GWAS) in diverse ethnic populations have revealed eleven single nucleotide polymorphisms (SNPs) linked to telomere length. Two of these, rs398652 and rs621559, have prognostic value and could be used as genetic markers. This review describes current knowledge concerning telomerase activity and telomere length as well as significant polymorphisms in HBV-related HCC patients. In particular, to cast light on genotype-phenotype interactions, we used SNPnexus to evaluate effects of the two SNPs on risk of disease and complex disorders.
