Scientists scan 100 sperm from same man and find huge DNA differences
For the first time, scientists have obtained genetic blueprints of almost 100 sperm from a single individual.
The results confirm what scientists already know, that every sperm is different because of the way their inherited DNA is shuffled. First place! Even sperm cells from the same man have big genetic differences, a study has shown.
The process, known as recombination, mixes up genes passed down by a man's mother and father and increases genetic diversity.
Each of the 91 sperm studied showed an average of 23 recombination, or mixing, events. But individual sperm varied greatly in the way they experienced spontaneous genetic mutations.
Every sperm contained between 25 and 36 ‘new’ mutations, not seen in other body cells.
‘For the first time we were able to generate an individual recombination map and mutation rate for each of several sperm from one person,’ said Professor Behr
Two sperm were found to be missing entire chromosomes, the protein-bound packages of DNA that contain the genes.
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The entire genomes of 91 human sperm from one man have been sequenced by Stanford University researchers. The results provide a fascinating glimpse into naturally occurring genetic variation in one individual, and are the first to report the whole-genome sequence of a human gamete - the only cells that become a child and through which parents pass...
The 'race' betweeen human sperm to the eggs might just look like a bunch of wriggling tadpoles - but it makes a big difference which sperm wins. Even sperm cells from the same man have big genetic differences, a study has shown. For the first time, scientists have obtained genetic blueprints of almost 100 sperm from a single individual.
( via dailymail.co.uk )