chr21-43058876-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PP2BP4

The NM_000071.3(CBS):​c.1316G>A​(p.Arg439Gln) variant causes a missense 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R439W) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 0)

Consequence

CBS
NM_000071.3 missense

Scores

2
6
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:2

Conservation

PhyloP100: 1.40

Publications

9 publications found
Variant links:
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

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ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 107 curated pathogenic missense variants (we use a threshold of 10). The gene has 4 curated benign missense variants. Gene score misZ: 0.8318 (below the threshold of 3.09). Trascript score misZ: NaN (below the threshold of 3.09). GenCC associations: The gene is linked to classic homocystinuria.
BP4
Computational evidence support a benign effect (MetaRNN=0.42296112).

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.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CBS
NM_000071.3
MANE Select
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 17NP_000062.1P35520-1
CBS
NM_001178008.3
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 17NP_001171479.1P35520-1
CBS
NM_001178009.3
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 18NP_001171480.1P35520-1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CBS
ENST00000398165.8
TSL:1 MANE Select
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 17ENSP00000381231.4P35520-1
CBS
ENST00000352178.9
TSL:1
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 17ENSP00000344460.5P35520-1
CBS
ENST00000359624.7
TSL:1
c.1316G>Ap.Arg439Gln
missense
Exon 14 of 18ENSP00000352643.3P35520-1

Frequencies

GnomAD3 genomes
Cov.:
0
GnomAD2 exomes
AF:
0.0000234
AC:
4
AN:
171116
AF XY:
0.0000330
show subpopulations
Gnomad AFR exome
AF:
0.0000997
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000430
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
Cov.:
0
GnomAD4 genome
Cov.:
0
Alfa
AF:
0.0000913
Hom.:
0
ExAC
AF:
0.0000169
AC:
2

ClinVar

ClinVar submissions
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
1
2
Classic homocystinuria (3)
-
2
-
not provided (2)
-
1
-
Familial thoracic aortic aneurysm and aortic dissection (1)
-
1
-
HYPERHOMOCYSTEINEMIA, THROMBOTIC, CBS-RELATED (1)
-
1
-
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.075
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Uncertain
0.12
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D
Eigen
Benign
-0.27
Eigen_PC
Benign
-0.19
FATHMM_MKL
Benign
0.33
N
LIST_S2
Uncertain
0.96
D
M_CAP
Uncertain
0.28
D
MetaRNN
Benign
0.42
T
MetaSVM
Uncertain
0.29
D
MutationAssessor
Benign
1.9
L
PhyloP100
1.4
PrimateAI
Benign
0.37
T
PROVEAN
Benign
-1.1
N
REVEL
Uncertain
0.60
Sift
Benign
0.13
T
Sift4G
Benign
0.29
T
Polyphen
0.21
B
Vest4
0.34
MVP
0.72
MPC
0.41
ClinPred
0.10
T
GERP RS
4.7
PromoterAI
0.0054
Neutral
Varity_R
0.51
gMVP
0.39
Mutation Taster
=0/100
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs756467921; hg19: chr21-44478986; API