Aboriginal Australian Genome

Scientists have used a lock of hair from an Aboriginal man of the early 20th century to isolate DNA for a sample with no European or Western contribution, and have subsequently sequenced and demonstrated that the original Australians descended from Asian populations about 50,000 years ago.

Prehistoric Mammal Hair

Two strands of hair from an unidentified mammal species have been discovered encased in a piece of 100-million-year-old amber, revealing that they are remarkably similar to the hairs of mammals today and have changed little over time.

Research Reveals Why Hair Turns Gray

Researchers at the Federation of American Societies for Experimental Biology (FASEB) have discovered the reason that hair turns gray as we age.

Gray hair results from a natural build-up over time of hydrogen peroxide (H₂O₂) in hair follicles, essentially bleaching the hair from within. This accumulation is cause by a reduction of a certain enzyme called catalase that breaks down hydrogen peroxide into water and oxygen. Hair follicles cannot repair the damage caused by hydrogen peroxide because of low levels of other enzymes methionine sulfoxide reductase (MSR) A and B that normally serve this function.

At the same time, the high levels of hydrogen peroxide and low levels of MSR A and B also disrupt the formation of the enzyme tyrosinase, which is responsible for the production of the natural pigment melanin. Researchers also speculate that a similar process is responsible for loss of pigment in certain skin conditions such as leukoderma.

These results were published in a recent edition of the FASEB Journal.

Source: ScienceDaily