3-183017313-CTT-C

Variant names:

• chr3-183017313-CTT-C
• NM_020166.5:c.2000_2001delAA

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_020166.5(MCCC1):​c.2000_2001delAA​(p.Lys667SerfsTer48) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: MCCC1 NM_020166.5 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.867
• Publications: 0 publications found

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]

MCCC1-AS1 (HGNC:40366): (MCCC1 antisense RNA 1)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 6 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-183017313-CTT-C is Pathogenic according to our data. Variant chr3-183017313-CTT-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2676446.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020166.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCCC1	NM_020166.5	MANE Select	c.2000_2001delAA	p.Lys667SerfsTer48	frameshift	Exon 18 of 19	NP_064551.3
	MCCC1	NM_001363880.1		c.1673_1674delAA	p.Lys558SerfsTer48	frameshift	Exon 17 of 18	NP_001350809.1	E9PHF7
	MCCC1	NM_001293273.2		c.1649_1650delAA	p.Lys550SerfsTer48	frameshift	Exon 16 of 17	NP_001280202.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCCC1	ENST00000265594.9	TSL:1 MANE Select	c.2000_2001delAA	p.Lys667SerfsTer48	frameshift	Exon 18 of 19	ENSP00000265594.4	Q96RQ3
	MCCC1	ENST00000492597.5	TSL:1	c.1673_1674delAA	p.Lys558SerfsTer48	frameshift	Exon 17 of 18	ENSP00000419898.1	E9PHF7
	MCCC1	ENST00000497830.5	TSL:1	n.*1597_*1598delAA		non_coding_transcript_exon	Exon 16 of 17	ENSP00000420088.1	F2Z3E2

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	3-methylcrotonyl-CoA carboxylase 1 deficiency (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.87

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

Other links and lift over

hg19: chr3-182735101;