12-22055268-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_018686.6(CMAS):​c.380T>C​(p.Ile127Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000424 in 1,605,334 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

CMAS
NM_018686.6 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.493

Publications

0 publications found
Variant links:
Genes affected
CMAS (HGNC:18290): (cytidine monophosphate N-acetylneuraminic acid synthetase) This gene encodes an enzyme that converts N-acetylneuraminic acid (NeuNAc) to cytidine 5'-monophosphate N-acetylneuraminic acid (CMP-NeuNAc). This process is important in the formation of sialylated glycoprotein and glycolipids. This modification plays a role in cell-cell communications and immune responses. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2016]
CMAS Gene-Disease associations (from GenCC):
  • intellectual disability
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.078231424).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CMASNM_018686.6 linkc.380T>C p.Ile127Thr missense_variant Exon 2 of 8 ENST00000229329.7 NP_061156.1 Q8NFW8-1
CMASNR_135117.2 linkn.466T>C non_coding_transcript_exon_variant Exon 2 of 7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CMASENST00000229329.7 linkc.380T>C p.Ile127Thr missense_variant Exon 2 of 8 1 NM_018686.6 ENSP00000229329.2 Q8NFW8-1
CMASENST00000534981.5 linkn.380T>C non_coding_transcript_exon_variant Exon 2 of 7 1 ENSP00000446239.1 Q8NFW8-2
CMASENST00000538498.1 linkc.-98T>C 5_prime_UTR_variant Exon 1 of 4 3 ENSP00000440605.1 F5GYM0
CMASENST00000535610.5 linkn.261-187T>C intron_variant Intron 1 of 4 5 ENSP00000439404.1 F5H296

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152236
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000162
AC:
4
AN:
246942
AF XY:
0.0000225
show subpopulations
Gnomad AFR exome
AF:
0.00
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:
0.0000356
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000440
AC:
64
AN:
1453098
Hom.:
0
Cov.:
28
AF XY:
0.0000387
AC XY:
28
AN XY:
723098
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33196
American (AMR)
AF:
0.00
AC:
0
AN:
43986
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25958
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39590
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85114
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53388
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.0000570
AC:
63
AN:
1106018
Other (OTH)
AF:
0.00
AC:
0
AN:
60098
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152236
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41476
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000330
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 20, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.380T>C (p.I127T) alteration is located in exon 2 (coding exon 2) of the CMAS gene. This alteration results from a T to C substitution at nucleotide position 380, causing the isoleucine (I) at amino acid position 127 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.071
BayesDel_addAF
Benign
-0.30
T
BayesDel_noAF
Benign
-0.56
CADD
Benign
16
DANN
Benign
0.73
DEOGEN2
Benign
0.078
T
Eigen
Benign
-0.59
Eigen_PC
Benign
-0.45
FATHMM_MKL
Benign
0.18
N
LIST_S2
Benign
0.77
T
M_CAP
Benign
0.0011
T
MetaRNN
Benign
0.078
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.25
N
PhyloP100
0.49
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.070
N
REVEL
Benign
0.070
Sift
Benign
0.64
T
Sift4G
Benign
0.60
T
Polyphen
0.0
B
Vest4
0.17
MVP
0.30
MPC
1.0
ClinPred
0.021
T
GERP RS
2.8
PromoterAI
0.017
Neutral
Varity_R
0.022
gMVP
0.41
Mutation Taster
=93/7
polymorphism

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

Publications

Other links and lift over

dbSNP: rs371108787; hg19: chr12-22208202; API