rs12021720

Two SNPedia users have self reported the (T;T) genotype with no apparent consequences. It was first noted in a patient with documented in omim. A Japanese patient with the intermediate form of maple syrup urine disease 2 showed a compound heterozygote for both * the apparently causative C->G transversion at nucleotide 309 DBT gene (I37M) * this G->A transition in exon 9 (G323S) which with no obvious consequences

C;T

a relatively common variant, which is linked to Maple Syrup Urine Disease, but appears harmless. In 1998 this paper published about a patient with MSUD who had 2 mutations "The third patient was a compound heterozygote for a C to G transversion at nucleotide 309 in exon 4 and a G to A transition at nucleotide 1165 in exon 9, causing an Ile-to-Met substitution at amino acid 37 and a Gly-to-Ser substitution at amino acid 323." It is that second mutation (Gly-to-Ser substitution at amino acid 323 also known as rs12021720) which was found in your data. It isn't clear from the paper if that mutation was somehow the cause of MSUD, influences its progression, or is completely harmless. In more recent years we have some additional information about this mutation, we now know it's frequency in caucasian population. In your report it is mentioned that the (C;T) that you have is found in 15.3% of all caucasians. As a result it is exceedingly unlikely that this directly causes anything as significant as MSUD, however it may still have lesser consequences when combined with other variants. A SNPedia user has now self reported the (T;T) genotype making it very unlikely that this snp has significant consequences.

T;T

Two SNPedia users have reported this genotype with no apparent consequences.