rs138432416

Variant names:

• chr21-43058935-C-G
• rs138432416
• NM_000071.3:c.1257G>C

Your query was ambiguous. Multiple possible variants found:

• chr21-43058935-C-G
• chr21-43058935-C-T

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP4_Moderate BP6_Very_Strong BP7

The NM_000071.3(CBS):​c.1257G>C​(p.Leu419Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. L419L) has been classified as Benign.

• Frequency: Genomes: not found (cov: 0)
• Consequence: CBS NM_000071.3 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: 0.816
• Publications: 1 publications found

Genes affected

CBS (HGNC:1550): (cystathionine beta-synthase) The protein encoded by this gene acts as a homotetramer to catalyze the conversion of homocysteine to cystathionine, the first step in the transsulfuration pathway. The encoded protein is allosterically activated by adenosyl-methionine and uses pyridoxal phosphate as a cofactor. Defects in this gene can cause cystathionine beta-synthase deficiency (CBSD), which can lead to homocystinuria. This gene is a major contributor to cellular hydrogen sulfide production. Multiple alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Feb 2016]

CBS Gene-Disease associations (from GenCC):

• classic homocystinuria

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, PanelApp Australia, ClinGen, Genomics England PanelApp

ACMG classification

Our verdict: Benign. The variant received -11 ACMG points.

• BP4: Computational evidence support a benign effect (REVEL=0.054).
• BP6: Variant 21-43058935-C-G is Benign according to our data. Variant chr21-43058935-C-G is described in ClinVar as Likely_benign. ClinVar VariationId is 795979.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.816 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CBS	NM_000071.3	c.1257G>C	p.Leu419Leu	synonymous_variant	Exon 14 of 17	ENST00000398165.8	NP_000062.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CBS	ENST00000398165.8	c.1257G>C	p.Leu419Leu	synonymous_variant	Exon 14 of 17	1	NM_000071.3	ENSP00000381231.4

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 0

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Benign:1

Oct 24, 2024

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED Benign:1

Dec 05, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.60
CADD	Benign	8.9
DANN	Benign	0.38
PhyloP100		0.82
PromoterAI		0.017	Neutral

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs138432416; hg19: chr21-44479045;