Instability of repetitive sequences is a hallmark of human cancer, and its enhancement has been linked to oxidative stress. Malondialdehyde is an endogenous product of oxidative stress that reacts with guanine to form the exocyclic adduct, pyrimido[1,2- alpha]purin-10(3H)-one (M1G). We used site-specifically modified single- and double-stranded vectors to investigate the mutagenic potential of ...

The hisT gene, one of six genes in which mutation causes derepression of the histidine operon in Salmonella typhimurium, is shown to code for a protein that is not essential for the growth of the bacteria. This is indicated by the characterization of particular classes of mutations in the hisT gene: amber mutations, frameshift mutations, and temperature-sensitive mutations that affect repressio...

Six ilvG (IlvG+) mutations of Escherichia coli K-12 were transferred to recombinant plasmids, and the DNA sequence of each mutation was determined. This analysis confirmed that expression of the ilvG gene product (acetohydroxy acid synthase II) requires the deletion of a single base pair or the addition of two base pairs within ilvG to displace a frameshift site present in wild-type E. coli K-1...

OBJECTIVES To analyse HIV Gag cleavage site (CS) and non-CS mutations in HIV non-B isolates from patients failing antiretroviral therapy. PATIENTS AND METHODS Twenty-one HIV isolates were obtained from patients infected with HIV subtype G during an outbreak in Russia 20 years ago. Most patients were failing antiretroviral therapy when genotyping was performed. RESULTS HIV Gag CS mutations a...

PURPOSE Bardet-Biedl syndrome (BBS) is genetically heterogeneous with 15 BBS genes currently identified, accounting for approximately 70% of cases. The aim of our study was to define further the spectrum of BBS mutations in a cohort of 44 European-derived American, 8 Tunisian, 1 Arabic, and 2 Pakistani families (55 families in total) with BBS. METHODS A total of 142 exons of the first 12 BBS-...

BACKGROUND Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is a genetic signature observed in 60% of sporadic colorectal cancers (CRCs). Unlike microsatellite unstable CRCs where hypermethylation of the DNA mismatch repair (MMR) gene hMLH1's promoter is causal, the precise cause of EMAST is not clearly defined but points towards hMSH3 deficiency. AIM To examine...

OBJECTIVE The aim of this study was to characterize the SCN1A mutation spectrum in Korean patients with Dravet syndrome. METHODS Twenty-nine patients diagnosed with Dravet syndrome at the Seoul National University Children's Hospital were included in the study. Direct sequencing and multiplex ligation-dependent probe amplification (MLPA) were used to identify SCN1A mutations. Mutations were c...