(Press-News.org) Several genes have been lost from the Y chromosome in humans and other mammals, according to research published in the open access journal Genome Biology. The study shows that essential Y genes are rescued by relocating to other chromosomes, and it identifies a potentially important genetic factor in male infertility.
The Y chromosome is dramatically smaller than the X chromosome and has already lost nearly all of the 640 genes it once shared with the X chromosome.
An extreme example of genes disappearing from the Y chromosome can be found in the Ryukyu spiny rat, which is indigenous to a single island in Japan. In this species, the Y chromosome has disappeared completely, with many Y-linked genes moving to either the X chromosome or non-sex chromosomes (autosomes). Until now, this was thought to be a peculiarity found in one isolated species, but new data suggest that the phenomenon of genes moving from sex chromosomes to autosomes is widespread among mammals, including humans.
Lead author Jennifer Hughes from the Whitehead Institute, USA, said: "Genes that have survived on the Y chromosome are extraordinarily long-lived and likely serve important biological functions. However, there are numerous exceptions where seemingly critical genes have been lost from the Y chromosome in certain mammals. In many cases, these genes were not actually eliminated but have found new homes in the genome.
"Now we've revealed four genes that have been lost from the Y chromosome and rescued by moving to other chromosomes. For the first time, we show that this has occurred in humans, as well as in a diverse range of other mammals. These relocated genes have hung around the genome because they are indispensable for normal development."
The team studied the genomes of humans, apes, rodents, cattle and marsupials, looking for evidence of genes that have relocated from the sex chromosomes to autosomes. By using evolutionary records of species divergences, they constructed family trees showing how certain genes had moved between chromosomes over time.
The four genes that were identified as having moved from the Y chromosome play key roles in protein synthesis and degradation within mammalian cells. The team found eight separate cases in different species where these genes moved from sex chromosomes to autosomes.
Copies of the EIF2S3 gene are found on the X and Y chromosomes of rodents, and the Y copy is a crucial player in the early steps of sperm production. In humans, this gene was found to be missing from the Y chromosome, but two copies were still present in the genome - one on the X chromosome and one on an autosome.
This suggests that, following the loss of the gene from the human Y chromosome, the X chromosome 'backed up' a copy of its EIF2S3 gene onto an autosome, indicating the importance of this gene. In humans, the autosomal copy of the gene showed increased activity in the testis compared to other tissues, suggesting an essential role in sperm production, and a possible genetic factor in male infertility.
Jennifer Hughes adds: "This research adds new complexities to our understanding of the role of sex chromosomes, genes and sex-specific characteristics, which warrant further investigation."
In order to obtain a broader survey of the impact that jumping-gene rescue of Y gene loss has had on genome evolution, high quality sex chromosome sequences from more species will need to be generated.
INFORMATION:
Media Contact
Joel Winston
Media Officer
BioMed Central
T: +44 (0)20 3192 2081
M: +44 (0)7766540147
E: Joel.Winston@biomedcentral.com
Notes to editor:
1. Research article
Jennifer F Hughes, Helen Skaletsky, Natalia Koutseva, Tatyana Pyntikova and David C Page
Sex chromosome-to-autosome transposition events counter Y-chromosome gene loss in mammals
Genome Biology 2015
doi: 10.1186/s13059-015-0667-4
For an embargoed copy of the research article, please contact Joel.Winston@biomedcentral.com
After embargo, article available at journal website here: http://dx.doi.org/10.1186/s13059-015-0667-4
Please name the journal in any story you write. If you are writing for the web, please link to the article. All articles are available free of charge, according to BioMed Central's open access policy.
2. Genome Biology serves the biological research community as an international forum for the dissemination, discussion and critical review of information about all areas of biology informed by genomic research. Key objectives are to provide a guide to the rapidly developing resources and technology in genomics and its impact on biological research, to publish large datasets and extensive results that are not readily accommodated in traditional journals, and to help establish new standards and nomenclature for post-genomic biology.
3. BioMed Central is an STM (Science, Technology and Medicine) publisher which has pioneered the open access publishing model. All peer-reviewed research articles published by BioMed Central are made immediately and freely accessible online, and are licensed to allow redistribution and reuse. BioMed Central is part of Springer Science+Business Media, a leading global publisher in the STM sector. http://www.biomedcentral.com
In what they believe to be the first survey of its kind in the United States, researchers at NYU Langone Medical Center have found that as many as 6 percent of adult New Yorkers who get "inked" -- in other words, those who get a tattoo -- have experienced some form of tattoo-related rash, severe itching or swelling that lasted longer than four months and, in some cases, for many years.
"We were rather alarmed at the high rate of reported chronic complications tied to getting a tattoo," says senior study investigator and NYU Langone dermatologist Marie Leger, MD, PhD, ...
Researchers from the Netherlands have explored how 3D printing can be used to help treat type 1 diabetes in results presented today, Thursday 28 May, in IOP Publishing's journal Biofabrication.
The 3D printing technique, known as bioplotting, has taken researchers one step closer to being able to help patients who experience severe hypoglycaemic events, commonly known as 'hypos'- a problem that affects about a third of people with type 1 diabetes according to Diabetes UK.
The paper describes how clusters of specialized cells responsible for the production of insulin ...
This news release is available in French. Alzheimer's disease is the most common form of dementia, affecting over 44 million people worldwide. Inside the brain, Alzheimer's disease is characterized by loss of neurons, and presence of abnormal tangles and plaques in the brain. Dr. Graham Collingridge, recently recruited from Bristol (U.K.) to the University of Toronto, has found that molecules that are strongly associated with Alzheimer's disease are important players in a process called long-term depression (LTD). LTD is a process through which the strength of synapses, ...
This news release is available in French. Pain has both physical and emotional components. Anxiety is common in people suffering from chronic pain, and people with anxiety are more likely to suffer from chronic pain. Dr. Min Zhuo and his team at the University of Toronto have found the biological basis for this link in the connections between neurons in a brain region known as the anterior cingulate cortex (ACC). Better yet, they have identified a molecule that can reduce chronic pain-related anxiety. Dr. Zhuo's latest results were presented at the 9th Annual Canadian ...
A longhorned beetle's sexy scent might make a female perk up her antennae. But when the males of several species all smell the same, a female cannot choose by cologne alone.
For these beetles to find a mate of the right species, timing is everything, according to research from a University of Arizona-led team.
"We found that beetles that produce the same pheromone are active at different times of day - and that beetles that are active at the same time of day produce different pheromones," said lead author Robert F. Mitchell, a UA research associate in the department ...
Fast Facts
People with schizophrenia often suffer from cognitive difficulties.
Transcranial direct current stimulation of the brain is widely considered safe and is being studied as a treatment for depression.
In a Johns Hopkins study of people with schizophrenia, transcranial direct current stimulation led to improvements in short-term memory.
Lightly stimulating the brain with electricity may improve short-term memory in people with schizophrenia, according to a new study by researchers at the Johns Hopkins University School of Medicine.
The ...
DALLAS, May 27, 2015 -- African Americans at lower socioeconomic levels, particularly women and younger adults, are at greater risk of heart disease and stroke than those in higher socioeconomic positions, according to research in the Journal of the American Heart Association.
Cardiovascular disease (CVD) is the No. 1 killer of all Americans, but the burden is greater for African Americans. According to the American Heart Association 2014 Statistical Update, nearly half of all African American adults have some form of CVD, and they are twice as likely as white adults ...
MINNEAPOLIS - New research suggests people with multiple sclerosis (MS) may have double the risk of dying early compared to people without MS, with those younger than 59 at a three times higher risk. The study is published in the May 27, 2015, online issue of Neurology®, the medical journal of the American Academy of Neurology.
"Despite studies that show MS survival may be improving over time, the more than 2.5 million people affected worldwide by this disabling disease still face a risk of dying earlier, specifically those who are diagnosed younger," said study ...
PITTSBURGH, May 27, 2015 - As the U.S. Supreme Court considers the legality of tax subsidies to buy health insurance under the Affordable Care Act (ACA), an investigation by the University of Pittsburgh Graduate School of Public Health, the RAND Corporation and Express Scripts provides an unprecedented look at prescription data gleaned from over a million initial enrollees.
The analysis is published online as a Web First article by Health Affairs and will also appear in the journal's June issue.
The study found that among people who enrolled in individual marketplaces, ...
It's both the bane of many parents and what has been called a major national vulnerability: the inability of many children to understand mathematics. Understanding that problem and developing strategies to overcome it is the research focus of Nicole McNeil, Alliance for Catholic Education (ACE) Associate Professor of Psychology at the University of Notre Dame, and the researchers in her lab.
A new paper by McNeil and Emily Fyfe, a former Notre Dame undergraduate who's now a doctoral student at Vanderbilt University, examines if the labels educators use to identify patterns ...
