NM_000071.3:c.1065G>C

Variant names:

• chr21-43060521-C-G
• rs748552493
• NM_000071.3:c.1065G>C
• CBS p.Ala355Ala

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Moderate BP6_Moderate BP7

The NM_000071.3(CBS):​c.1065G>C​(p.Ala355Ala) 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. A355A) 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: -2.50
• Publications: 0 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: ClinGen, Genomics England PanelApp, Orphanet, Myriad Women's Health, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (REVEL=0.025).
• BP6: Variant 21-43060521-C-G is Benign according to our data. Variant chr21-43060521-C-G is described in ClinVar as Likely_benign. ClinVar VariationId is 766244.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-2.5 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000071.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CBS	NM_000071.3	MANE Select	c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 17	NP_000062.1	P35520-1
	CBS	NM_001178008.3		c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 17	NP_001171479.1	P35520-1
	CBS	NM_001178009.3		c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 18	NP_001171480.1	P35520-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CBS	ENST00000398165.8	TSL:1 MANE Select	c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 17	ENSP00000381231.4	P35520-1
	CBS	ENST00000352178.9	TSL:1	c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 17	ENSP00000344460.5	P35520-1
	CBS	ENST00000359624.7	TSL:1	c.1065G>C	p.Ala355Ala	synonymous	Exon 12 of 18	ENSP00000352643.3	P35520-1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 0

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	0.18
DANN	Benign	0.41
PhyloP100		-2.5
PromoterAI		0.0040	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs748552493;

hg19: chr21-44480631;