From SNPedia
This is one of four SNPs in the first intron of the SNAP25 gene that have been correlated with increased intelligence based on studies of ~300 Caucasian subjects.[PMID 16801949]
In orientation to the dbSNP entry for this SNP, rather than as published, the (C;C) genotype averages ~2 PIQ points higher than the (C;T) genotype, which averages 2 PIQ points higher than the (T;T) genotype.[PMID 16801949]
For SNPs rs363039 - rs363043 - rs353016, respectively, the haplotype C-T-T is most associated with higher intelligence in children, whereas the haplotype C-C-T is most associated in adults (SNPs oriented as in dbSNP). [PMID 17908175]
| ? | (C;C) (C;T) (T;T) |
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