rs143225442

chr21-43056876-C-Achr21-43056876-C-T

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_Moderate BP6_Moderate BP7

The NM_000071.3(CBS):c.1479G>T(p.Thr493=) 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. T493T) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 0)
• Consequence: CBS NM_000071.3 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -2.33

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]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.44).
• BP6: Variant 21-43056876-C-A is Benign according to our data. Variant chr21-43056876-C-A is described in ClinVar as [Likely_benign]. Clinvar id is 1155565.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-2.33 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CBS	NM_000071.3	c.1479G>T	p.Thr493=	synonymous_variant	16/17	ENST00000398165.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CBS	ENST00000398165.8	c.1479G>T	p.Thr493=	synonymous_variant	16/17	1	NM_000071.3	P1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 0

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Feb 22, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.44
Cadd	Benign	0.058
Dann	Benign	0.59

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr21-44476986;