Browsing your own genome

Using deCODEme’s genome browser software and the raw genomic data from 23andme that deCODEme generously allowed me to import, I can analyse any of my family’s ~25,000 genes against one another and identify if any matches exist. For example, Chromosome 6, contains genes that determine whether or not someone would be a good organ donor for me or I for them. The figure below shows a screen capture of deCODEme’s excellent Genome Browser. Using Genome Browser, I can identify the similarity between my genome and any other publicly available genome. In addition, at my discretion, I can share with anyone who shares their genomic material with me privately, which for me is my family. (You may elect to not share with anyone at all or to share with family members only for privacy reasons). In the following figures, colored bars indicate the similarity between myself and the person indicated for the region on Chromosome 6.  

Genome matching between Johnathan Storlie and others on Chromosome 6. Diploid chromosomes like 6 contain two chromosomes and so three types of matching are possible between two individuals for any given nucleotide: Blue=low sharing, green=medium, magenta=high sharing (e.g. matching alleles of a gene)
Genome matching between Johnathan Storlie and others on Chromosome 6. Diploid chromosomes like 6 actually contain two chromosomes containing two copies of each gene and so three types of matching are possible between two individuals for any given nucleotide: Blue=low sharing, green=medium, magenta=high sharing (e.g. matching alleles of a gene)

 Not surprisingly, my sister Jill and my brother David have areas on diploid chromosome 6 which are 100% identical for both copies of the chromosome. This indicates that, with respect to this region, the haploid chromosome on my mother’s gamete was identical for my sibling and me, and the haploid chromosome on my father’s gamete was identical for my sibling and me (magenta). In other areas, we received opposite haploid chromosomal material from both gametes and thus have no more genetic similarity that our parents have with one another in these regions (blue=low/no sharing) on either copy of our diploid chromosome. In other areas we only share lengthy sequences of SNPs in common on one strand of the two copies of diploid chromosome 6 (green). Note the red and blue bands that surround nucleotide sequences at about 30,000 base pairs in the first figure. Between these two bands lie the histocompatibility genes which control whether or not a person is a match for an organ donation. If I were in need of an organ, unfortunately, neither my sister Jillellyn, nor my brother David, would be ideal candidates because the magenta area (indicating 100% identity) does not extend into this region for either one of them. I still have one brother left to test, and I have about a 1 in 5 chance of a perfect match over the entire histocompatibility region.  

Matching DNA SNPs in MHC region of Chromosome 6 shows I have no perfect organ donors in tested members of immediate family or with Watson, Venter, and Stephans. Blue=low DNA sharing, green=medium sharing, purple=high sharing.
Of the 3 billion nucleotides that represent the average haploid human genome, there are relatively few common nucleotide variants. Here we have zoomed in on Chromosome 6, comparing Johnathan Storlie's SNPs with those indicated. For reference, human genome sequence build 36 is shown.

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