That assumption was based on studying mitochondrial lineage - a small part of the genome , or dna , that is passed exclusively from mothers to offspring .
这一假设基于线粒体世系研究也就是基因或是脱氧核糖核酸的一小部分物质,同时仅仅由母亲传给子嗣。
Many of the key molecules for life have a specific direction , or handedness : dna twists to the right , amino acids to the left .
构成生命体的许多关键分子都有一个特定的导向,或者说是旋向性:脱氧核糖核酸右旋,氨基酸左旋。
A gene is a strand of dna that holds the code for the amino acids that make proteins . And proteins do the work of the body .
Scientists at the university of aberdeen say a genetic switch - dna which turns genes on or off within cells - regulates appetite and thirst .
英国阿伯丁大学的科学家们指出基因开关-即控制细胞内基因的脱氧核糖核酸(dna)-能调节人的饥渴。
But after studying dna from inside the cell nucleus , using samples from 19 polar and 18 brown bears , frank hailer of germany 's biodiversity and climate research centre and colleagues reached a very different conclusion .
In research presented sunday at the international conference on alzheimer 's disease in vienna , dr. roses and his team looked at the area of dna surrounding the apoe gene .
These are a normal by-product of mitochondrial activity , but are usually mopped up by special enzymes before they can escape and cause harm-for instance , by damaging a cell 's dna .
Since there have been adverse results using viruses as agents to transfer genes into humans , the researchers instead chose to transfer the hmaxi-k gene using " naked dna , " or dna stripped of any proteins .
Instead , all the dna present in a sample is sequenced at the same time ; then clever computer software works out the contribution of different microbes to the genetic soup .
Other , more established oncologists point out that cui 's mice are genetically uniform ; humans , with their distinct dna differences , would run a deadly risk of the donated cells attacking their host , even if they aren 't rejected first .