11-102606663-TA-AG

Variant names:

• chr11-102606663-TA-AG
• NM_004771.4:c.824_825delTAinsCT
• MMP20 p.Val275Ala

Variant summary

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

The NM_004771.4(MMP20):​c.824_825delTAinsCT​(p.Val275Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V275L) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MMP20 NM_004771.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.748
• Publications: 0 publications found

Genes affected

MMP20 (HGNC:7167): (matrix metallopeptidase 20) Proteins of the matrix metalloproteinase (MMP) family are involved in the breakdown of extracellular matrix in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes, such as arthritis and metastasis. Most MMP's are secreted as inactive proproteins which are activated when cleaved by extracellular proteinases. The protein encoded by this gene degrades amelogenin, the major protein component of dental enamel matrix, and thus thought to play a role in tooth enamel formation. A mutation in this gene, which alters the normal splice pattern and results in premature termination of the encoded protein, has been associated with amelogenesis imperfecta. This gene is part of a cluster of MMP genes located on chromosome 11q22.3. [provided by RefSeq, Aug 2011]

MMP20 Gene-Disease associations (from GenCC):

• amelogenesis imperfecta hypomaturation type 2A2

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• amelogenesis imperfecta type 2

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004771.4. 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
	MMP20	NM_004771.4	MANE Select	c.824_825delTAinsCT	p.Val275Ala	missense	N/A	NP_004762.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MMP20	ENST00000260228.3	TSL:1 MANE Select	c.824_825delTAinsCT	p.Val275Ala	missense	N/A	ENSP00000260228.2	O60882
	MMP20	ENST00000544938.1	TSL:3	n.280_281delTAinsCT		non_coding_transcript_exon	Exon 3 of 5

Frequencies

GnomAD3 genomes Cov.: 32

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

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.75

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr11-102477394;