Sequence variability at three major histocompatibility complex (MHC) genes (DQB, DRA, and MHC-I) of cetaceans was investigated in order to get an overall understanding of cetacean MHC evolution. Little sequence variation was detected at the DRA locus, while extensive and considerable variability were found at the MHC-I and DQB loci. Phylogenetic reconstruction and sequence comparison revealed extensive sharing of identical MHC alleles among different species at the three MHC loci examined. Comparisons of phylogenetic trees for these MHC loci with the trees reconstructed only based on non-PBR sites revealed that allelic similarity/identity possibly reflected common ancestry and were not due to adaptive convergence. At the same time, trans-species evolution was also evidenced that the allelic diversity of the three MHC loci clearly pre-dated species divergence events according to the relaxed molecular clock. It may be the forces of balancing selection acting to maintain the high sequence variability and identical alleles in trans-specific manner at the MHC-I and DQB loci.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00239-009-9272-z | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Genetic susceptibility of diffuse large B-cell lymphoma: a meta genome-wide association study in Asian population.
Leukemia
December 2024
Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, Guangdong, China.
Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy and the most common form of non-Hodgkin lymphoma (NHL) that occurs worldwide. To discover risk factors and pathogenesis of DLBCL, we performed the largest GWAS of DLBCL to date in samples of East Asian ancestry, consisting of 2,888 patients with DLBCL and 12,458 controls. The meta-analysis identified three novel loci, rs2233434 on 6p21.
View Article and Find Full Text PDFInsights from the timber rattlesnake (Crotalus horridus) genome for MHC gene architecture and evolution in threatened rattlesnakes.
J Hered
December 2024
Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, Ohio, 43210 USA.
Conservation of threatened species can benefit from an evaluation of genes in the Major Histocompatibility Complex (MHC), whose loci encode proteins that bind pathogens and are often under strong selection to maintain diversity in immune response to diseases. Despite this gene family's importance to disease resistance, little is known about these genes in reptiles including snakes. To address this issue, we assembled and annotated a highly-contiguous genome assembly for the timber rattlesnake (Crotalus horridus), a pit viper which is threatened or endangered in parts of its range, and analyzed this new genome along with three other rattlesnake genomes to characterize snake MHC loci.
View Article and Find Full Text PDFThe search to understand the development of the chicken immune system: Differences in expression of MHC class I loci and waves of thymocytes as evolutionary relics?
Dev Biol
December 2024
University of Edinburgh, Institute for Immunology and Infection Research, Edinburgh, United Kingdom. Electronic address:
Chickens are renowned as a model for embryogenesis but have also been responsible for crucial advances in virology, cancer research and immunology. However, chickens are best known as a major source of animal protein for human nutrition, with roughly 80 billion chickens alive each year supplying meat and eggs, the vast majority part of a global poultry industry. As a result, avian immunology been studied intensively for over 60 years, and it has become clear that a major genetic locus in chickens determining resistance to infectious disease and response to vaccines is the major histocompatibility complex (MHC).
View Article and Find Full Text PDFHigh rates of MHC mismatches in HLA matched unrelated donor/recipient pairs and potential impact on hematopoietic cell transplant outcome.
Hum Immunol
December 2024
Diagnostic Laboratories and Blood Research Institute, Versiti, Milwaukee, WI, USA. Electronic address:
Introduction: Donors for patients requiring hematopoietic cell transplant (HCT) are selected based on matching genetic sequences encoding the antigen recognition domain of specific HLA loci. However, differences in transplant outcomes in fully matched unrelated HCT compared with sibling HCT suggest that other genetic regions within the major histocompatibility complex (MHC) may contribute to HCT outcomes.
Methods: We sequenced the non-classical MHC loci (NCML) HLA-E, -F, -G, -H, MICA and MICB on a well-characterized retrospective cohort of 157 unrelated donor/recipient HCT pairs to determine the extent of MHC mismatching in matched pairs.
The genetic landscape of autism spectrum disorder in an ancestrally diverse cohort.
NPJ Genom Med
December 2024
Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
Article Synopsis
- - The study focused on understanding the genetic causes of autism spectrum disorder (ASD) by sequencing the DNA of 754 individuals from 195 families, identifying a total of 38,834 new genetic variants.
- - Researchers discovered 92 potentially harmful genetic variations in 73 known genes among 68 individuals with ASD, along with 158 likely damaging variants in 120 other candidate genes.
- - The findings enhance our knowledge of ASD genetics, revealing patterns linked to brain development and cellular signaling, which could aid in diagnosing and developing treatments for the disorder.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!