Monday, June 13, 2011

Parents Passing More Mutations Than Expected

With advances in human genomics, a new discovery makes a lot of sense where we were missing the links all these days. Humans pass on their genes to their kids and during this process, there are many chnages that occur in the DNA. Such chnages include recombination at the time of formation of gametes, also referred to as eggs and sperms. Scientits were only able to find the mutations in kids that were passed on by the parents all these days. Now with this new study they have found that the mutauiohn also occur in sperms and egges that lead to new mutaions or changes in kids, which were not seen in parents.

On an average, only 1 in every 100 million letters of DNA is altered each generation. This study shows that each one of us receives approximately 60 new mutations in our genome from our parents.

The authors of the study says

We human geneticists have theorised that mutation rates might be different between the sexes or between people," explains Dr Matt Hurles, Senior Group Leader at the Wellcome Trust Sanger Institute, who co-led the study with scientists at Montreal and Boston, "We know now that, in some families, most mutations might arise from the mother, in others most will arise from the father. This is a surprise: many people expected that in all families most mutations would come from the father, due to the additional number of times that the genome needs to be copied to make a sperm, as opposed to an egg.
Professor Philip Awadalla,who also co-led the project and is at University of Montreal explained: Today, we have been able to test previous theories through new developments in experimental technologies and our analytical algorithms. This has allowed us to find these new mutations, which are like very small needles in a very large haystack.

Authjors cannot tell from this study whether the variation in numbers of new mutations is the result of differences in mutation processes between parents, or differences between individual sperm and eggs within a parent, as the study looked at a single child. New techniques and algorithms can help address such issues as the impact of parental age and different environment exposures on rates of new mutations.

A person with a high natural mutation rate might be at greater risk of misdiagnosis of a genetic disease because the samples used for diagnosis might contain mutations that are not present in other cells in their body: most of their cells would be unaffected.

1 comment:

  1. I think this study is going to change alot of things the way we arrive at conclusions. NextGen sequencing is providing a lot of data everyday.