Science has long established the Y-male chromosome as being male-specific, but new research confers the chromosome as possessing two genes that do the bulk of the heavy lifting during reproduction.
Tag: genes
Researchers Identify Gene Variations Linked to Male and Female Infertility
Identification of genetic variations in the genes coding for the hormone FSH may provide new treatments for male and female infertility, according to work presented at the European Congress of Endocrinology in Copenhagen. A group of researchers at the University of Muenster has characterised gene variations which may improve treatment for almost half of infertile men, as well as allowing tailored treatment for women undergoing assisted reproduction.
Why Fathers Really Matter
MOTHERHOOD begins as a tempestuously physical experience but quickly becomes a political one. Once a woman’s pregnancy goes public, the storm moves outside. Don’t pile on the pounds! Your child will be obese. Don’t eat too little, or your baby will be born too small. For heaven’s sake, don’t drink alcohol. Oh, please: you can sip some wine now and again. And no matter how many contradictory things the experts say, don’t panic. Stress hormones wreak havoc on a baby’s budding nervous system. Read full article.
Mother’s Genes May Explain Why Women Outlive Men
An evolutionary “loophole” might explain why males of many species live shorter lives than their female counterparts, a new study finds.
The loophole lies in the mitochondria, the energy-generating parts of our cells. The mitochondria have their own DNA, separate from the DNA that resides in the nucleus of the cell that we usually think of when we think of the genome. In almost all species, the mitochondria DNA is passed down solely from mother to child, without input from dad.
This direct line of inheritance may allow harmful mutations to accumulate, according to a new study detailed today (Aug. 2) in the journal Current Biology. Ordinarily, natural selection helps keep harmful mutations to a minimum by ensuring they’re not passed down to offspring. But if a mitochondrial DNA mutation is dangerous only to males and doesn’t harm females, there’s nothing to stop mom from passing it to her daughters and sons.
“If a mitochondrial mutation pops up that is benign in females, or a mutation pops up that is beneficial to females, this mutation will slip through the gates of natural selection and go through to the next generation,” said study researcher Damian Dowling, an evolutionary biologist at Monash Univeristy in Australia.
The result: a load of mutations that don’t harm females, but add up to a shorter life span for males.
Sperm Sequencing Could Help Fight Infertility
Not all sperm are created equal. The first genetic comparison of individual sperm cells has revealed just how diverse they can be. The technology used to study these tiny cells might also be used to study cancer and allow doctors to screen eggs for in vitro fertilisation.
To investigate how much variety there is in one man’s sperm, Stephen Quake, Jianbin Wang and their colleagues at Stanford University in California compared sperm cells from a single semen sample.
Analysing the genes of individual cells is notoriously tricky, though. “It’s hard to express how difficult single cell experiments are,” says Adam Auton at the Albert Einstein College of Medicine in New York. To perform genetic sequencing, you need to amplify, or make lots of copies of the genes within a cell to have enough to analyse. The compounds needed for amplification produce chemical by-products that can make the analysis more difficult.
Read full article.
Should MPs sanction ‘three-parent babies’?
There are about 50 known mitochondrial diseases, which are passed on in genes coded by mitochondrial (as opposed to nuclear) DNA. They range in severity, but for most there is no cure. It is therefore understandable that scientists and affected families want research into “three-parent embryo” techniques to go ahead. But there are good reasons for caution.
To begin with, this is not about finding a cure. It is about preventing people with mitrochondrial disease being born. These new technologies, even if they work, will do nothing for the thousands of people already suffering from these diseases, or for those who will be born with it in the future. And for affected couples there are already alternative solutions, including adoption and egg donation. Apart from this, I’m left with some big questions.
Will it work? This technology uses similar “nuclear transfer” techniques to those used in “therapeutic cloning” for embryonic stem cells – which has thus far failed to deliver, and animal-human cytoplasmic hybrids (“cybrids”). The wild claims made about cybrids by the biotechnology industry, research scientists, patient-interest groups and science journalists duped parliament into licensing animal-human hybrid research in 2008. Few today will remember Gordon Brown’s empty promises of cybrids offering “a profound opportunity to save and transform millions of lives” or how this research would be “an inherently moral endeavour that can save and improve the lives of thousands and over time millions of people”. But the measure was supported in a heavily whipped vote as part of the human fertilisation and embryology bill, now the HFE Act. Yet cybrids are now a farcical footnote in history. They have not worked. Ironically, it was in that same act of parliament that provision for this new research was also made
Grandma Explains Breast Cancer Fertility Link
A University of Utah team found that mutations in BRCA1 and BRCA2 gene, which raise the risk of women having breast and ovarian cancer are also linked to greater fertility.