Many studies of human populations have used the male-specific region of the Y chromosome (MSY) as a marker, but MSY sequence variants have traditionally been subject to ascertainment bias. Also, dating of haplogroups has relied on Y-specific short tandem repeats (STRs), involving problems of mutation rate choice, and possible long-term mutation saturation. Next-generation sequencing can ascertain single nucleotide polymorphisms (SNPs) in an unbiased way, leading to phylogenies in which branch-lengths are proportional to time, and allowing the times-to-most-recent-common-ancestor (TMRCAs) of nodes to be estimated directly. Here we describe the sequencing of 3.7 Mb of MSY in each of 448 human males at a mean coverage of 51×, yielding 13,261 high-confidence SNPs, 65.9% of which are previously unreported. The resulting phylogeny covers the majority of the known clades, provides date estimates of nodes, and constitutes a robust evolutionary framework for analyzing the history of other classes of mutation. Different clades within the tree show subtle but significant differences in branch lengths to the root. We also apply a set of 23 Y-STRs to the same samples, allowing SNP- and STR-based diversity and TMRCA estimates to be systematically compared. Ongoing purifying selection is suggested by our analysis of the phylogenetic distribution of nonsynonymous variants in 15 MSY single-copy genes.
Background: Chronic infections, such as periodontitis, have been associated with an increased risk for atherosclerosis and coronary artery disease. The aim of this study was to investigate biopsy samples of coronary and internal mammary arteries for the presence of putative pathogenic bacteria (Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Tannerella forsythensis), Chlamydia pneumoniae, and human cytomegalovirus (CMV).Methods: Patients with a diagnosis of coronary artery disease were included in the study. Fifteen coronary arteries with atherosclerosis and 15 internal mammary arteries without clinically assessable atherosclerotic degeneration were investigated. Both groups of specimens were obtained during coronary artery bypass grafting surgery. In all cases, the coronary and mammary artery specimens were taken from the same patient. The detection of periodontal pathogens, C. pneumoniae, and CMV was done by polymerase chain reaction analysis.Results: Bacterial DNA was found in nine of 15 (60%) coronary artery biopsy samples: P. gingivalis in eight (53.33%), A. actinomycetemcomitans in four (26.67%), P. intermedia in five (33.33%), and T. forsythensis in two (13.33%) samples; CMV was detected in 10 (66.67%) samples, and C. pneumoniae was detected in five (33.33%) samples. Some of the samples contained more than one type of bacteria. Periodontal pathogens were not detected in internal mammary artery biopsies, whereas CMV was present in seven (46.67%) samples and C. pneumoniae was present in six (40%) samples.Conclusion: The absence of putative pathogenic bacteria in internal mammary arteries, which are known to be affected rarely by atherosclerotic changes, and their presence in a high percentage of atherosclerotic coronary arteries support the concept that periodontal organisms are associated with the development and progression of atherosclerosis.
X-linked dilated cardiomyopathy (XLDC) is a familial heart disease presenting in young males as a rapidly progressive congestive heart failure, without clinical signs of skeletal myopathy. This condition has recently been linked to the dystrophin gene in some families and deletions encompassing the genomic region coding for the first muscle exon have been detected. In order to identify the defect responsible for this disease at the molecular level and to understand the reasons for the selective heart involvement, a family with a severe form of XLDC was studied. In the affected members, no deletions of the dystrophin gene were observed. Analysis of the muscle promoter, first exon and intron regions revealed the presence of a single point mutation at the first exon-intron boundary, inactivating the universally conserved 5′ splice site consensus sequence of the first intron. This mutation introduced a new restriction site for Msel, which cosegregates with the disease in the analyzed family. Expression of the major dystrophin mRNA isoforms (from the muscle-, brain- and Purkinje cell-promoters) was completely abolished in the myocardium, while the brain- and Purkinje cell- (but not the muscle-) isoforms were detectable in the skeletal muscle. Immunocytochemical studies with anti-dystrophin antibodies showed that the protein was reduced in quantity but normally distributed in the skeletal muscle, while it was undetectable in the cardiac muscle. These findings indicate that expression of the muscle dystrophin isoform is critical for myocardial function and suggest that selective heart involvement in dystrophin-linked dilated cardiomyopathy is related to the absence, in the heart, of a compensatory expression of dystrophin from alternative promoters.
The proportion of Europeans descending from Neolithic farmers ∼10 thousand years ago (KYA) or Palaeolithic hunter-gatherers has been much debated. The male-specific region of the Y chromosome (MSY) has been widely applied to this question, but unbiased estimates of diversity and time depth have been lacking. Here we show that European patrilineages underwent a recent continent-wide expansion. Resequencing of 3.7 Mb of MSY DNA in 334 males, comprising 17 European and Middle Eastern populations, defines a phylogeny containing 5,996 single-nucleotide polymorphisms. Dating indicates that three major lineages (I1, R1a and R1b), accounting for 64% of our sample, have very recent coalescent times, ranging between 3.5 and 7.3 KYA. A continuous swathe of 13/17 populations share similar histories featuring a demographic expansion starting ∼2.1–4.2 KYA. Our results are compatible with ancient MSY DNA data, and contrast with data on mitochondrial DNA, indicating a widespread male-specific phenomenon that focuses interest on the social structure of Bronze Age Europe.
The oral cavity has been proposed as a reservoir for H. pylori that could be responsible for the refractoriness of gastric infection to triple therapy (antibiotics, antimicrobials, and proton pump inhibitors). The aim of this study was to evaluate the efficiency of combined periodontal and triple therapy vs. triple therapy alone, in gastric H. pylori eradication in persons with H. pylori in the subgingival biofilm. Individuals positive for H. pylori in their gastric and oral samples, as determined by nested PCR, were treated either with periodontal and triple therapy or with triple therapy alone. Our results indicate that 77.3% of those treated with the combined therapy exhibited successful eradication of gastric H. pylori, compared with 47.6% who underwent only triple therapy. Analysis of these data suggests that periodontal treatment in combination with systemic therapy could be a promising approach to increasing the therapy’s efficacy and decreasing the risk of infection recurrence.
Background The existence of an association between cardiovascular diseases (CVDs) and apical periodontitis (AP) remains unclear because results obtained from previous clinical studies and reviews are inconsistent or inconclusive. Objective To conduct an umbrella review to determine whether there is an association between CVDs and the prevalence of the AP in adults. Methods The protocol of the review was registered in the PROSPERO database (CRD42020185753). The literature search was conducted using the following electronic databases: Clarivate Analytics’ Web of Science Scopus, PubMed, and Cochrane Database of Systematic Reviews (CDSR), from inception to May, 2020, with no language restrictions. Systematic reviews with or without meta‐analysis that evaluated the association between CVDs and AP were included. Other types of studies, including narrative reviews, were excluded. Two reviewers independently performed a literature search, data extraction, and quality assessment of included studies. Any disagreements or doubts were resolved by a third reviewer. The quality of the reviews was assessed using the AMSTAR 2 tool (A measurement tool to assess systematic reviews), with 16 items. A final categorization of the systematic reviews classified each as of “high” , “moderate” , “low” , or “critically low” quality. Results Four systematic reviews were included in the current review. Three reviews were graded by AMSTAR 2 as “moderate ” quality, whereas one review was graded as “critically low ” quality. Discussion Only one systematic review included a meta‐analysis. Substantial heterogeneity amongst the primary studies included within each systematic review was notable in preventing pooled analysis. Conclusions From the limited and moderate to low quality evidence available, the current umbrella review concluded that a weak association exists between CVDs and AP. In future, well‐designed, longitudinal clinical studies with long‐term follow‐up are required.