21-43067923-T-A

Variant names:

• chr21-43067923-T-A
• rs234714
• NM_000071.3:c.316+586A>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001321072.1(CBS):​c.-145A>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 0)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CBS NM_001321072.1 5_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.0100
• Publications: 25 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: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet, Myriad Women’s Health, Genomics England PanelApp

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001321072.1. 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.316+586A>T		intron	N/A	NP_000062.1	P35520-1
	CBS	NM_001321072.1		c.-145A>T		5_prime_UTR	Exon 1 of 14	NP_001308001.1
	CBS	NM_001178008.3		c.316+586A>T		intron	N/A	NP_001171479.1	P35520-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CBS	ENST00000398165.8	TSL:1 MANE Select	c.316+586A>T		intron	N/A	ENSP00000381231.4	P35520-1
	CBS	ENST00000352178.9	TSL:1	c.316+586A>T		intron	N/A	ENSP00000344460.5	P35520-1
	CBS	ENST00000359624.7	TSL:1	c.316+586A>T		intron	N/A	ENSP00000352643.3	P35520-1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 54360 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 30842

African (AFR) AF: 0.00 AC: 0 AN: 458

American (AMR) AF: 0.00 AC: 0 AN: 7436

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 1224

East Asian (EAS) AF: 0.00 AC: 0 AN: 1350

South Asian (SAS) AF: 0.00 AC: 0 AN: 14064

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 2474

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 888

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 24042

Other (OTH) AF: 0.00 AC: 0 AN: 2424

GnomAD4 genome Cov.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.010
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs234714; hg19: chr21-44488033;