21-43062945-C-T

Variant names:

• chr21-43062945-C-T
• rs76292057
• NM_000071.3:c.954+8G>A

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Strong BP6_Very_Strong

The NM_000071.3(CBS):​c.954+8G>A variant causes a splice region, 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)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CBS NM_000071.3 splice_region, intron
• Scores: Splicing: ADA: 0.001863
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: -0.0710
• 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: ClinGen, Genomics England PanelApp, Orphanet, Myriad Women's Health, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Benign. The variant received -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.72).
• BP6: Variant 21-43062945-C-T is Benign according to our data. Variant chr21-43062945-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 136672.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.954+8G>A		splice_region intron	N/A	NP_000062.1	P35520-1
	CBS	NM_001178008.3		c.954+8G>A		splice_region intron	N/A	NP_001171479.1	P35520-1
	CBS	NM_001178009.3		c.954+8G>A		splice_region intron	N/A	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.954+8G>A		splice_region intron	N/A	ENSP00000381231.4	P35520-1
	CBS	ENST00000352178.9	TSL:1	c.954+8G>A		splice_region intron	N/A	ENSP00000344460.5	P35520-1
	CBS	ENST00000359624.7	TSL:1	c.954+8G>A		splice_region intron	N/A	ENSP00000352643.3	P35520-1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD2 exomes AF: 0.000494 AC: 124 AN: 250980 AF XY: 0.000376

Gnomad AFR exome AF: 0.00745

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 10 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 4

African (AFR) AC: 0 AN: 0

American (AMR) AC: 0 AN: 0

Ashkenazi Jewish (ASJ) AC: 0 AN: 0

East Asian (EAS) AC: 0 AN: 0

South Asian (SAS) AC: 0 AN: 0

European-Finnish (FIN) AC: 0 AN: 0

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 6

Other (OTH) AF: 0.00 AC: 0 AN: 4

GnomAD4 genome Cov.: 0

Alfa AF: 0.00163 Hom.: 1

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

ClinVar submissions

Significance: Benign/Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	3	not specified (3)
-	-	2	Classic homocystinuria (2)
-	-	2	not provided (2)
-	-	1	HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.72
CADD	Benign	6.4
DANN	Benign	0.89
PhyloP100		-0.071

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0019
dbscSNV1_RF	Benign	0.0080
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: rs76292057;

hg19: chr21-44483055;