9-21802657-G-A

Variant names:

• chr9-21802657-G-A
• NM_002451.4:c.-92G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_002451.4(MTAP):​c.-92G>A variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 29)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MTAP NM_002451.4 5_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.451
• Publications: 0 publications found

Genes affected

MTAP (HGNC:7413): (methylthioadenosine phosphorylase) This gene encodes an enzyme that plays a major role in polyamine metabolism and is important for the salvage pathway of both adenine and methionine. The encoded enzyme is deficient in many cancers. Multiple alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Sep 2021]

MTAP Gene-Disease associations (from GenCC):

• diaphyseal medullary stenosis-bone malignancy syndrome

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Genomics England PanelApp, G2P, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen

ENSG00000264545 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MTAP	NM_002451.4	c.-92G>A		5_prime_UTR_variant	Exon 1 of 8	ENST00000644715.2	NP_002442.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MTAP	ENST00000644715.2	c.-92G>A		5_prime_UTR_variant	Exon 1 of 8		NM_002451.4	ENSP00000494373.1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1297310 Hom.: 0 Cov.: 19 AF XY: 0.00 AC XY: 0 AN XY: 650904

African (AFR) AF: 0.00 AC: 0 AN: 29330

American (AMR) AF: 0.00 AC: 0 AN: 41278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24764

East Asian (EAS) AF: 0.00 AC: 0 AN: 37536

South Asian (SAS) AF: 0.00 AC: 0 AN: 80198

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51404

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4428

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 973704

Other (OTH) AF: 0.00 AC: 0 AN: 54668

GnomAD4 genome Cov.: 29

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	8.9
DANN	Benign	0.84
PhyloP100		0.45
PromoterAI		-0.069	Neutral

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: chr9-21802656;