MTR Gene

Definition:5-methyltetrahydrofolate-homocysteine methyltransferase

Official Symbol:MTR

 Chromosome:1


Gene Size: 105245 bp   235025341..235130585


No Exons:33

 Location : 1q43

Description:

MTR gene provides information for making an enzyme called methionine synthase.This enzyme, also known as cobalamin-dependent methionine synthase, catalyzes the final step in methionine biosynthesis

Disease :

Mutations in MTR have been identified as the underlying cause of methylcobalamin deficiency complementation group G,and Homocystinuria  Disease.In this disease more than 15 mutations in the MTR gene have been identified in people with homocystinuria. Many of these mutations lead to the production of an abnormally small, nonfunctional version of methionine synthase. Other mutations change single amino acids in the enzyme, which disrupts the enzyme's activity. For example, one of the most common mutations replaces the amino acid proline with the amino acid leucine at position 1173 (written as Pro1173Leu or P1173L). Without functional methionine synthase, homocysteine cannot be converted to methionine. As a result, homocysteine builds up in the bloodstream and methionine is depleted. Some of the excess homocysteine is excreted in urine. Researchers have not determined how altered levels of homocysteine and methionine lead to the health problems associated with homocystinuria.

MTHFR Gene

Definition:5,10-methylenetetrahydrofolate reductase (NADPH)

Official Symbol:MTHFR

Chromosome:1


Gene Size: 20329 bp complement(11768374..11788702)


No Exons:12

Location : 1p36.3



Description:

MTHFR gene codes for an enzyme called methylenetetrahydrofolate reductase,which plays vital role in amino acid processing and protein building blocks ,Methylenetetrahydrofolate reductase catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a cosubstrate for homocysteine remethylation to methionine

Disease :

Mutations in the gene MTHFR causes disease called Homocystinuria,Homocystinuria, also known as Cystathionine beta synthase deficiency, is an inherited disorder of the metabolism of the amino acid methionine, often involving cystathionine beta synthase. It is an inherited autosomal recessive trait, About 24 mutation in MTHFR gene have been identified in people with homocystinuria,Most of these mutaions are single amino acids in methylenetetrahydrofolate reductase.These substitutions disrupt the function of the enzyme, and may inactivate it completely,Without methylenetetrahydrofolate reductase, homocysteine cannot be converted to methionine. As a result, homocysteine builds up in the bloodstream and methionine is depleted. Some of the excess homocysteine is excreted in urine. Researchers have not determined how altered levels of homocysteine and methionine lead to the health problems associated with homocystinuria.

Homocystinuria, What is it?