Objective(s) Varicocele is associated with impaired testicular function and male infertility, but the molecular mechanisms by which fertility is affected have not been satisfactorily explained. The aim of our study was to investigate whether or not the polymerase gamma (POLG) polymorphism is associated with Iranian varicocele patients.    Materials and Methods We determined the POLG CAG repe...

Retroviral reverse transcriptases (RTs) frequently switch templates during DNA synthesis, which can result in mutations and recombination. The relative rates of in vivo RT template switching during RNA- and DNA-dependent DNA synthesis are unknown. To determine the relative rates of RT template switching during copying of RNA and DNA templates, we constructed spleen necrosis virus-based retrovir...

Repetitive DNA elements are mutational hotspots in the genome, and their instability is linked to various neurological disorders and cancers. Although it is known that expanded trinucleotide repeats can interfere with DNA replication and repair, the cellular response to these events has not been characterized. Here, we demonstrate that an expanded CAG/CTG repeat elicits a DNA damage checkpoint ...

The DNA-binding domain of c-Myb consists of three homologous tandem repeats of 52 amino acids. The structure of the third (C-terminal) repeat obtained by NMR analysis has a conformation related to the helix-turn-helix motif. To identify the role of each repeat in the sequence recognition of DNA, we analyzed specific interactions between c-Myb and DNA by measuring binding affinities for systemat...

Duplication and repeat-deletion are the basic models of errors occurring during DNA replication from the viewpoint of formal languages. During DNA replication, subsequences of a strand of DNA may be copied several times (duplication) or skipped (repeat-deletion). Iterated duplication and repeat-deletion have been well-studied, but little is known about single-step duplication and repeat-deletio...

TAL (transcription activator-like) effectors, secreted by phytopathogenic bacteria, recognize host DNA sequences through a central domain of tandem repeats. Each repeat comprises 33 to 35 conserved amino acids and targets a specific base pair by using two hypervariable residues [known as repeat variable diresidues (RVDs)] at positions 12 and 13. Here, we report the crystal structures of an 11.5...

Mitochondrial DNA polymerase gamma (POLG) is the only DNA polymerase involved in maintaining the mitochondrial genome. Recent studies demonstrated an association of CAG repeat polymorphism in the second exon of POLG gene with the risk of cancer. We investigated the CAG repeat variability in the POLG gene in tumor and non-tumor tissues from colorectal cancer patients and in DNA samples isolated ...

SUMMARY With the increasing availability of high-density methylation microarrays, there has been growing interest in analysis of DNA methylation data. We have developed CpGassoc, an R package that can efficiently perform the statistical analysis needed for increasingly large methylation datasets. CpGassoc is a modular, expandable package with functions to perform rapid analyses of DNA methylati...

BACKGROUND Expandable screws have greater pullout strength than conventional screws. The purpose of this study was to compare the biomechanical stability provided by a new built-in expandable anterior spinal fixation system with that of 2 commonly used anterior fixation systems, the Z-Plate and the Kaneda, in a porcine partial vertebral corpectomy model. METHODS Eighteen porcine thoracolumbar...