In 2005, about 20 percent (82,600 million gallons per day (Mgal/d)) of total national water withdrawals (about 410,000 Mgal/d) came from groundwater sources. (All 2010 water use information is from the report Estimated use of water in the United States in 2010.) Very little saline groundwater was used in 2005.
The MTHFR nucleotide at position 677 in the gene has two possibilities: C (cytosine) or T (thymine). C at position 677 (leading to an alanine at amino acid 222) is the normal allele. The 677T allele (leading to a valine substitution at amino acid 222) encodes a thermolabile enzyme with reduced activity.
1 The MTHFR gene C677T and A1298C polymorphisms were associated with an increased risk of bladder cancer in a Turkish population. 2  Meta-analysis. 3  In the Chinese Han population, the TT genotype for the MTHFR C677T gene appeared to be associated with increased coronary artery disease risk. Molecular genetic study was performed, and demonstrated that the patient was heterozygous for the CBS gene with the compound mutations T353 M and D444 N, and homozygous for the mutation C677T in the methylenetetrahydropholate reductase (MTHFR) gene.