rs766591766

chr5-71649153-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_022132.5(MCCC2):c.1273A>G(p.Met425Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,102 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M425I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: MCCC2 NM_022132.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 3.13

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.84

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MCCC2	NM_022132.5	c.1273A>G	p.Met425Val	missense_variant	14/17	ENST00000340941.11
MCCC2	NM_001363147.1	c.1159A>G	p.Met387Val	missense_variant	13/16

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MCCC2	ENST00000340941.11	c.1273A>G	p.Met425Val	missense_variant	14/17	1	NM_022132.5	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152232 Hom.: 0 Cov.: 32

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: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 251466 Hom.: 0 AF XY: 0.0000368 AC XY: 5 AN XY: 135908

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: 0.000196

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461870 Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8 AN XY: 727232

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152232 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74374

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000414

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.0000330 AC: 4

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

3-methylcrotonyl-CoA carboxylase 2 deficiency Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Nov 11, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	May 03, 2021	This sequence change replaces methionine with valine at codon 425 of the MCCC2 protein (p.Met425Val). The methionine residue is highly conserved and there is a small physicochemical difference between methionine and valine. This variant is present in population databases (rs766591766, ExAC 0.02%) but has not been reported in the literature in individuals with a MCCC2-related disease. In summary, this variant is a rare missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on mRNA splicing suggest that this variant may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.47
BayesDel_addAF	Uncertain	0.057	T
BayesDel_noAF	Uncertain	0.10
Cadd	Benign	15
Dann	Benign	0.97
DEOGEN2	Pathogenic	0.92	D;.
Eigen	Benign	-0.15
Eigen_PC	Benign	-0.12
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.84	D;D
MetaSVM	Uncertain	0.69	D
MutationAssessor	Pathogenic	3.0	M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Uncertain	-3.3	D;D
REVEL	Pathogenic	0.70
Sift	Uncertain	0.0010	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		0.25	B;.
Vest4		0.39
MutPred		0.77		Gain of methylation at K424 (P = 0.1241);.;
MVP		0.89
MPC		0.28
ClinPred		0.78	D
GERP RS		1.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.81
gMVP		0.93

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

Other links and lift over

dbSNP: rs766591766; hg19: chr5-70944980;