Following betaine supplementation, the activity of BHMT
increased in pigs fed diets which were either adequate (Emmert et al.
RFLP analysis was used to identify BHMT 742G>A (35), CBS 699C>T (22), PON1 163T>A, PON1 575A>G, RFC1 80G>A (32), TCII 776C>G, and TCII 67A>G (29).
Eleven SNPs (MTHFR 677C>T, MTHFR 1298A>C, MTR 2756A>G, MTRR 66A>G, CBS 699C>T, BHMT 742G>A, RFC1 80G>A, TCII 67A>G, TCII 776C>G, PON1 163T>A, and PON1 575A>G) and 1 insertion polymorphism (CBS 844ins68) are included.
1) Nonstandard abbreviations: Hcy, homocysteine; MTHFR, methylenetetrahydrofolate reductase; BHMT, betaine-homocysteine methyltransferase; MTR, methionine synthase; MTRR, methionine synthase reductase; CBS, cystathionine [beta]-synthase; SNP, single-nucleotide polymorphism; TCII, transcobalamin II; RFC1, reduced folate carrier-1; PON1, paraoxonase-1; RFLP, restriction fragment-length polymorphism; MS, mass spectrometry; MALDI-TOF; matrix-assisted laser desorption/ionization time of flight; ddNTP, dideoxynucleotide triphosphate; and dNTP, deoxynucleotide triphosphate.
The authors speculate that the stratification method they employed may have inadvertently grouped families by one or more unidentified cofactors correlated with folate supplementation, or that the BHMT
polymorphism may create a genetic variant that promotes overactivity of the folate metabolic cycle, given the high folate levels achieved during supplementation.
Accordingly the company has classified and is now reporting BHMT
as a discontinued business for all current and prior periods.
RESULTS: Only single nucleotide polymorphisms (SNPs) in BHMT were significantly associated in the overall data set; this significance was strongest when mothers took folate-containing nutritional supplements before conception.
CONCLUSIONS: BHMT rs3733890 is significantly associated in our data set, whereas MTHFR rs1801133 is not a major risk factor.
Three genes that degrade homocysteine (MTR, BHMT, and CBS) were more thoroughly genotyped based on HapMap Release 19 (International HapMap Project 2005) tagging single nucleotide polymorphisms (SNPs) and location in the gene (Figure 2).
These tests were performed on all SNPs for the narrow and broad phenotypes in the overall data set as well as those subdivided by maternal folate supplementation, BHMT allele transmission, and MTHFR allele transmission.
The initial analysis of the entire data set for 28 SNPs in 11 genes (Table 3) found associations: BHMT rs3733890 (narrow PDT p = 0.
334 ASTEC UNDERGROUND 807 ATLAS COPCO BHMT
100 AVANTI INTERNATIONAL 708 BAKER HUGHES DRILLING FLUIDS--IP 428 BAROID INDUSTRIAL DRILLING PRODUCTS 831 BOYER, INC.