rs398124352

chr3-183039088-C-Achr3-183039088-C-Gchr3-183039088-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3_Moderate PP5

The NM_020166.5(MCCC1):c.1315G>T(p.Val439Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000142 in 1,614,104 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V439M) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: MCCC1 NM_020166.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 5.84

Genes affected

MCCC1 (HGNC:6936): (methylcrotonyl-CoA carboxylase subunit 1) This gene encodes the large 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. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_020166.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-183039088-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 95940.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Likely_pathogenic=1, Uncertain_significance=2}.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.851
• PP5: Variant 3-183039088-C-A is Pathogenic according to our data. Variant chr3-183039088-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1210430.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MCCC1	NM_020166.5	c.1315G>T	p.Val439Leu	missense_variant	12/19	ENST00000265594.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MCCC1	ENST00000265594.9	c.1315G>T	p.Val439Leu	missense_variant	12/19	1	NM_020166.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152216 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: 0.00

Gnomad FIN AF: 0.0000942

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000318 AC: 8 AN: 251428 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135878

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.000323

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000150 AC: 22 AN: 1461888 Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.000150

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152216 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74360

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: 0.0000942

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

3-methylcrotonyl-CoA carboxylase 1 deficiency Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Invitae	Sep 08, 2023	This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 439 of the MCCC1 protein (p.Val439Leu). This variant is present in population databases (rs398124352, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with MCCC1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1210430). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt MCCC1 protein function. This variant disrupts the p.Val439 amino acid residue in MCCC1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 22642865, 31901042; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 22, 2021	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.61
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.40
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D;D;D;D;D
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D
M_CAP	Benign	0.074	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	4.3	H;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-3.0	D;D;.;.;D
REVEL	Pathogenic	0.66
Sift	Pathogenic	0.0	D;D;.;.;D
Sift4G	Uncertain	0.0020	D;D;D;D;.
Polyphen		0.88	P;P;.;.;P
Vest4		0.88
MutPred		0.76		Loss of methylation at K436 (P = 0.08);.;.;.;.;
MVP		0.87
MPC		0.31
ClinPred		1.0	D
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.89
gMVP		0.90

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: rs398124352; hg19: chr3-182756876;