Genetics & Molecular Biology

MOLECULAR MARKERS AND GENOME SEQUENCING IN CROP IMPROVEMENT. Molecular techniques, in particular the applications of molecular markers, have been used to scrutinize DNA sequence variation(s) in and among the crop species and create new sources of genetic variation by introducing new and favorable traits from landraces and related crop species. Molecular markers What are they? A marker is a gene or piece of DNA with easily identified phenotype such that cells or individuals with different alleles are distinguishable. For example a gene with a known function or a single nucleotide change in DNA Or A readily detectable sequence of DNA or protein whose inheritance can be monitored
A million years is a blink of an eye in evolution but that doesn't mean newer genes matter less in life itself.    
"My two dads" is no longer just a lousy TV show.  Using induced pluripotent stem cell technology (controversy-free!) scientists have produced male and female mice from two fathers.

It isn't part of any cultural agenda, the intent was to preserve endangered species, but obviously it opens up the possibility of same-sex couples having their own genetic children.  The authors caution that the "generation of human iPS cells still requires significant refinements prior to their use for therapeutic purposes."
Does science really need to give Tiger Woods/Brett Favre an excuse?

"Sorry, sweetheart, I didn't mean to bang anything with a hole and a heart beat that came my way/text that chick pictures of my junk. But you have to forgive me because it's in my DNA. Oh look, it's tee time/game time again."
A new study was released today in JAMA which looked at, in part, mitochondrial DNA overreplication in a sample of ten autistic children between the ages of 2 and 5 and ten matched controls.  Giulivi et al. found that 5 of the 10 autistic children and 2 of the control children had mitchondrial DNA overreplication.

In the comments section of a previous post, the question was raised of how autism is diagnosed in the samples being studied. This new study allows an opportunity to look at how carefully the sample is selected and controls matched to the sample.
Researchers conducting genome-wide association studies say they have discovered 30 new genes determine the age of sexual maturation in women - and many of those genes also act on body weight regulation or biological pathways related to fat metabolism.

Menarche, the onset of first menstruation in girls, indicates the attainment of reproductive capacity and is a widely used marker of pubertal timing. Age of menarche varies widely and is highly dependent on nutritional status and early menarche is associated with many adverse health outcomes later in life, including breast cancer, endometrial cancer, obesity, type 2 diabetes and cardiovascular disease, as well as shorter adult stature.

Not having had any serious biological training I have to go to Wikipedia and Google to learn the basics. And I’m often surprised to find that concepts everyone uses don’t have good consensus amongst scientists. When reading the Wikipedia entry for “gene”, it occurs to me that if the concept didn’t predate the discovery of DNA, it would not exist.

At the very least, it would look much different than “a locatable region of genomic sequence, corresponding to a unit of inheritance” (call this the “standard definition”).

The ethical issues surrounding unchecked human embryonic stem cell research are not going away any time soon, regardless of which political party occupies Congress or the White House.   

Given that, researchers have devised various alternatives and now scientists at the Max Planck Institute for Molecular Genetics in Berlin have added one more.   They have managed to convert amniotic fluid cells into induced pluripotent stem cells (iPS cells). These amniotic fluid-derived iPS cells are hardly distinguishable from embryonic stem cells - however, they 'remember' where they came from.
Oxytocin, dubbed the "cuddle hormone" because of its importance in bonding ,  is best known for its role in childbirth and breastfeeding, and animal studies have shown that it may also be important in monogamous social relationships. Recently, economic research in humans implicated oxytocin in trust and empathy.

Additional animal research shows that oxytocin may relieve stress and anxiety in social settings and may be more rewarding than cocaine to new mothers.
Proteins are the indispensable catalytic workhorses, carrying out the processes essential to life in today's sophisticated organisms, but long ago ribonucleic acid (RNA) reigned supreme.

Researchers have produced an atomic picture that shows how two of these very old molecules interact with each other and it provides a rare glimpse into the transition from an ancient, RNA-based world to our present, protein-catalyst dominated world.