rs773774134

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5

The NM_022132.5(MCCC2):​c.568C>T​(p.His190Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,613,966 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

MCCC2
NM_022132.5 missense

Scores

14
4
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6U:1

Conservation

PhyloP100: 7.62
Variant links:
Genes affected
MCCC2 (HGNC:6937): (methylcrotonyl-CoA carboxylase subunit 2) This gene encodes the small subunit of 3-methylcrotonyl-CoA carboxylase. This enzyme functions as a heterodimer and catalyzes the carboxylation of 3-methylcrotonyl-CoA to form 3-methylglutaconyl-CoA. Mutations in this gene are associated with 3-Methylcrotonylglycinuria, an autosomal recessive disorder of leucine catabolism. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, May 2018]

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1
In a domain CoA carboxyltransferase N-terminal (size 257) in uniprot entity MCCB_HUMAN there are 13 pathogenic changes around while only 0 benign (100%) in NM_022132.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.986
PP5
Variant 5-71604412-C-T is Pathogenic according to our data. Variant chr5-71604412-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 198252.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=1, Pathogenic=3}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
MCCC2NM_022132.5 linkuse as main transcriptc.568C>T p.His190Tyr missense_variant 6/17 ENST00000340941.11 NP_071415.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
MCCC2ENST00000340941.11 linkuse as main transcriptc.568C>T p.His190Tyr missense_variant 6/171 NM_022132.5 ENSP00000343657 P1Q9HCC0-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152090
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
GnomAD3 exomes
AF:
0.0000159
AC:
4
AN:
251464
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135906
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 SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000889
AC:
13
AN:
1461876
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
727236
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000812
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000360
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152090
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74306
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000278
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:6Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

3-methylcrotonyl-CoA carboxylase 2 deficiency Pathogenic:2Uncertain:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsNov 29, 2023- -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 01, 2021This sequence change replaces histidine with tyrosine at codon 190 of the MCCC2 protein (p.His190Tyr). The histidine residue is highly conserved and there is a moderate physicochemical difference between histidine and tyrosine. This variant is present in population databases (rs773774134, ExAC 0.001%). This missense change has been observed in individual(s) with 3-methylcrotonyl-CoA carboxylase deficiency (PMID: 16010683). ClinVar contains an entry for this variant (Variation ID: 198252). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. Experimental studies have shown that this missense change affects MCCC2 function (PMID: 16010683). This variant disrupts the p.His190 amino acid residue in MCCC2. Other variant(s) that disrupt this residue have been observed in individuals with MCCC2-related conditions (PMID: 16010683, 17968484), which suggests that this may be a clinically significant amino acid residue. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Likely pathogenic, criteria provided, single submittercurationSIB Swiss Institute of BioinformaticsOct 15, 2018This variant is interpreted as Likely Pathogenic, for MCC2 deficiency, autosomal recessive. The following ACMG Tag(s) were applied: PM2 => Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium. PP3 => Multiple lines of computational evidence support a deleterious effect on the gene or gene product. PS3 => Well-established functional studies show a deleterious effect (https://www.ncbi.nlm.nih.gov/pubmed/16010683). -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)May 04, 2015- -
Pathogenic, criteria provided, single submitterclinical testingGeneDxSep 20, 2018The H190Y variant in the MCCC2 gene has been reported previously in association with 3-methylcrotonyl-CoA carboxylase deficiency, in an affected individual who was homozygous for the H190Y variant (Dantas et al., 2005). This variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). The H190Y variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. In-silico analyses, including protein predictors and evolutionary conservation, support a deleterious effect, and expression studies found that H190Y is associated with severely decreased 3-methylcrotonyl-CoA carboxylase activity (Dantas et al., 2005). Missense variants in the same codon (H190R) and nearby residues (R193C and R193H) have been reported in the Human Gene Mutation Database in association with 3-methylcrotonyl-CoA carboxylase deficiency (Stenson et al., 2014), supporting the functional importance of this region of the protein. We interpret H190Y as a pathogenic variant. -
Methylcrotonyl-CoA carboxylase deficiency Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpSep 10, 2022Variant summary: MCCC2 c.568C>T (p.His190Tyr) results in a conservative amino acid change located in the Acetyl-coenzyme A carboxyltransferase, N-terminal domain (IPR011762) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.6e-05 in 251464 control chromosomes. c.568C>T has been reported in the literature as a homozygous genotype in at-least one individual affected with a mild phenotype of Methylcrotonyl-CoA Carboxylase Deficiency (example, Dantas_2005). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function in-vitro (example, Dantas_2005). The most pronounced variant effect results in absence of normal 3-methylcrotonyl-CoA carboxylase (MCC) activity. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 (VUS, n=1; P/LP, n=3). Based on the evidence outlined above, the variant was classified as likely pathogenic. -
MCCC2-related disorder Pathogenic:1
Likely pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJul 15, 2024The MCCC2 c.568C>T variant is predicted to result in the amino acid substitution p.His190Tyr. This variant was reported in the homozygous state in one mildly affected individual with 3-methylcrotonyl-CoA carboxylase deficiency (Dantas et al 2005. PubMed ID: 16010683). In an in vitro expression study, the p.His190Tyr substitution was reported to abolish enzyme activity (Dantas et al 2005. PubMed ID: 16010683). An alternative substitution of the same amino acid (p.His190Arg) was reported along with a second likely pathogenic MCCC2 variant in an individual with 3-methylcrotonyl-CoA carboxylase deficiency (Uematsu et al. 2007. PubMed ID: 17968484). This variant is reported in 0.0033% of alleles in individuals of South Asian descent in gnomAD. This variant is interpreted as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.45
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.56
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.78
D;D;.
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.89
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.99
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
2.9
.;M;.
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.55
T
PROVEAN
Pathogenic
-5.7
.;D;D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
.;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
1.0, 0.92
.;D;P
Vest4
0.96
MutPred
0.91
Loss of catalytic residue at R188 (P = 0.0595);Loss of catalytic residue at R188 (P = 0.0595);Loss of catalytic residue at R188 (P = 0.0595);
MVP
0.99
MPC
0.56
ClinPred
0.97
D
GERP RS
5.6
Varity_R
0.94
gMVP
0.92

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs773774134; hg19: chr5-70900239; API