rs370071493

chr21-43058973-G-Achr21-43058973-G-C

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_Strong BP6_Very_Strong

The NM_000071.3(CBS):c.1224-5C>T variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency: Genomes: not found (cov: 0)
• Consequence: CBS NM_000071.3 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.0001251
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -0.151

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 Benign. Variant got -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.78).
• BP6: Variant 21-43058973-G-A is Benign according to our data. Variant chr21-43058973-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 509146.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CBS	NM_000071.3	c.1224-5C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000398165.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CBS	ENST00000398165.8	c.1224-5C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_000071.3	P1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD3 exomes AF: 0.0000138 AC: 3 AN: 216712 Hom.: 0 AF XY: 0.0000170 AC XY: 2 AN XY: 117578

Gnomad AFR exome AF: 0.000226

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

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

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Apr 26, 2017

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jul 30, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.78
Cadd	Benign	12
Dann	Benign	0.71

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00013
dbscSNV1_RF	Benign	0.0060
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

LitVar

Other links and lift over

dbSNP: rs370071493; hg19: chr21-44479083;