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Hi this message came up on my promethease report. However my raw data came from 23 and me not ancestry.com should I be worried ? Has anyone else got the same message with data from something other then ancestry.com ?

Someone please expand on this, I found this in my 23andme promethease report... I do have many of the symptoms associated with XYY syndrome.

If you would be willing to share your data, we are willing to look into this, since it may help define the difference between low quality data in a person's file (which can look like heterozygosity) and examples of true heterozygosity. Just email us via <info@promethease.com>. Greg (talk) 18:20, 8 February 2015 (UTC)

After receiving the Gs266 message, I contacted 23andMe customer service. Here's their response. "The double calls you are seeing on your Y chromosome correspond to the pseudoautosomal regions of the Y chromosome. In your 23andMe raw data, positions on the two ends of your X chromosome will have double calls. These areas are at positions less than 2710157 and greater than or equal to 154657830. These regions consist of genes that are found mostly on the tips of the short arm of both the X and Y chromosomes. These genes stand out for a couple of reasons. First, every individual has double copies of the genes in these regions (for males the genes are found on both the X and Y chromosome and for females the double copies are found on their X chromosomes). Also, these regions mimic the inheritance patterns of autosomal chromosomes and recombination events occur between the X and Y chromosomes in these regions. The double calls that you see in your raw data on the X chromosome are actually calls from these regions on both your X and Y chromosomes. The Human Genome Project labeled these particular SNP's as being on the X chromosome and it is widely accepted to report these genotypes in this fashion - even though they may be more clearly labeled as X/Y SNP's. So, these double calls in the pseudoautosomal regions are expected and not cause for a retest."