Dyslexia, as defined by an article in Wikipedia, is a type of reading disability that can be found in people at all intelligence levels (below, at and above average). Dyslexia is one of the most common childhood cognitive disorders, affecting perhaps 5% of school-age children.
The region of the genome that has probably the highest linkage to dyslexia is on chromosome 6p21-22, and harbors two clusters of genes. The two gene clusters are VMP/DCDC2/KAAG1, and, KIAA0319/TTRAP/THEM2. These two clusters of genes are linked and have numerous SNPs, and so far no functional SNPs (i.e. SNPs likely to directly influence dyslexia) have been found. Instead, several SNPs have been identified as the best surrogates marking alleles of higher risk. These SNPs include:
- In the DCDC2 gene [PMID 16385449]:
- In the KIAA0319 gene [PMID 17033633]:
- rs3212236, in the 5' flanking region
- rs761100, in the first intron
- rs4504469, in exon 4 [PMID 15717286]
- In the TTRAP gene [PMID 15514892]:
