CBS

is a	gene
is	mentioned by
Full name	cystathionine-beta-synthase
EntrezGene	875
PheGenI	875
VariationViewer	875
ClinVar	CBS
GeneCards	CBS
dbSNP	875
Diseases	CBS
SADR	875
HugeNav	875
wikipedia	CBS
google	CBS
gopubmed	CBS
EVS	CBS
HEFalMp	CBS
MyGene2	CBS
23andMe	CBS
UniProt	P35520
Ensembl	ENSG00000160200
OMIM	613381
# SNPs	94

	Max Magnitude	Chromosome position	Summary
rs1057516256	0	43,068,508
rs1057516552	0	43,072,158
rs1057516645	0	43,058,871
rs1057516895	0	43,056,888
rs1057517083	0	43,066,292
rs1057517198	0	43,072,174
rs1057517373	0	43,062,952
rs1057517435	0	43,065,231
rs1064793703	0	43,062,344
rs1064794540	0	43,060,499
rs11203172	0	43,060,005
rs117687681	0	43,060,481
rs121964962	3	43,062,988
rs121964963	3	43,066,260
rs121964964	0	43,066,353
rs121964965	3	43,066,279
rs121964966	0	43,066,264
rs121964967	3	43,059,299
rs121964968	0	43,053,920
rs121964969	0	43,063,931
rs121964970	0	43,065,645
rs121964971	0	43,058,215
rs121964972	4.5	43,060,528
rs121964973	0	43,065,481
rs12329764	0	43,063,138
rs12329790	0	44,483,184
rs138211175	0	43,058,919
rs139456571	0	43,065,269
rs140002610	0	43,066,300
rs147474549	0	43,066,294
rs148865119	0	43,072,048
rs149119723	0	43,063,943
rs1789953	0	43,062,826
rs1801181	0	43,060,506
rs199948079	0	43,072,032
rs2298758	0	43,065,417
rs234706	2.5	43,065,240	Influences folate metabolism
rs234709	0	43,066,854
rs234713	0	43,067,781
rs234714	0	43,067,923
rs234715	0	43,068,285	An snp on CBS, for cystathionine-β-synthase - it is one of the genes involved in the folate pathway.
rs2851391	0	43,067,294
rs28934275	0	43,063,931
rs28934891	0	43,058,862
rs28934892	0	43,058,927
rs34758144	0	43,058,472
rs372010465	0	43,060,475
rs375846341	3	43,058,970
rs377708532	0	43,066,354
rs398123151	3	43,062,344
... further results

The CBS gene encodes the enzyme called cystathionine beta-synthase. This enzyme acts in a chemical pathway and is responsible for using vitamin B6 to convert the amino acids homocysteine and serine to a molecule called cystathionine. Another enzyme then converts cystathionine to the amino acid cysteine, which is used to build proteins or is broken down and excreted in urine. Additionally, other amino acids, including methionine, are produced in this pathway.Genetics Home Ref

More than 150 mutations that cause homocystinuria have been identified in the CBS gene. The most common mutation substitutes the amino acid threonine for the amino acid isoleucine at position 278 in the enzyme (written as Ile278Thr or I278T; rs5742905). Another common mutation, which is the most frequent cause of homocystinuria in the Irish population, replaces the amino acid glycine with the amino acid serine at position 307 (written as Gly307Ser or G307S; rs121964972). These mutations disrupt the normal function of cystathionine beta-synthase. As a result, homocysteine and other potentially toxic compounds build up in the blood, and homocysteine is excreted in urine. Researchers have not determined how excess homocysteine leads to the signs and symptoms of homocystinuria.Genetics Home Ref

Homocystinuria is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.

Although people who carry one mutated copy and one normal copy of the CBS gene do not have homocystinuria, they are more likely than people without a CBS mutation to have shortages (deficiencies) of vitamin B12 and folic acid.Genetics Home Ref