Researchers two years ago built a library of more than 10 million variants in exomes.
While nuclear DNA is transferred to offspring by both parents, mtDNA is inherited from the mother alone.
Pictures of the Sooam Biotech Research Foundation, a world leader in pet cloning.
"Cloning provides a psychological alternative to the traditional method of just letting the pet go and keeping their memory."
A similar gene variant has been seen in some people who struggle with obesity
"Millions of years of evolution have produced far more protective mechanisms than we currently understand."
Research has found that patients of African descent require higher doses than those of European origins
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