chr22-32801728-G-C

Position:

• chr22-32801728-G-C

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_000362.5(TIMP3):​c.-274G>C variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000967 in 208,956 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00093 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0011 (1 hom.)
• Consequence: TIMP3 NM_000362.5 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.569

Genes affected

TIMP3 (HGNC:11822): (TIMP metallopeptidase inhibitor 3) This gene belongs to the TIMP gene family. The proteins encoded by this gene family are inhibitors of the matrix metalloproteinases, a group of peptidases involved in degradation of the extracellular matrix (ECM). Expression of this gene is induced in response to mitogenic stimulation and this netrin domain-containing protein is localized to the ECM. Mutations in this gene have been associated with the autosomal dominant disorder Sorsby's fundus dystrophy. [provided by RefSeq, Jul 2008]

SYN3 (HGNC:11496): (synapsin III) This gene is a member of the synapsin gene family. Synapsins encode neuronal phosphoproteins which associate with the cytoplasmic surface of synaptic vesicles. Family members are characterized by common protein domains, and they are implicated in synaptogenesis and the modulation of neurotransmitter release, suggesting a potential role in several neuropsychiatric diseases. The protein encoded by this gene shares the synapsin family domain model, with domains A, C, and E exhibiting the highest degree of conservation. The protein contains a unique domain J, located between domains C and E. Based on this gene's localization to 22q12.3, a possible schizophrenia susceptibility locus, and the established neurobiological roles of the synapsins, this family member may represent a candidate gene for schizophrenia. The TIMP3 gene is located within an intron of this gene and is transcribed in the opposite direction. Alternative splicing of this gene results in multiple splice variants that encode different isoforms. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.78).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000927 (141/152070) while in subpopulation NFE AF= 0.00137 (93/67924). AF 95% confidence interval is 0.00114. There are 0 homozygotes in gnomad4. There are 64 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High AC in GnomAd4 at 141 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TIMP3	NM_000362.5	c.-274G>C		5_prime_UTR_variant	1/5	ENST00000266085.7	NP_000353.1
SYN3	NM_003490.4	c.711+63187C>G		intron_variant		ENST00000358763.7	NP_003481.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TIMP3	ENST00000266085.7	c.-274G>C		5_prime_UTR_variant	1/5	1	NM_000362.5	ENSP00000266085	P1
SYN3	ENST00000358763.7	c.711+63187C>G		intron_variant		5	NM_003490.4	ENSP00000351614	P1
SYN3	ENST00000462268.1	n.225+63187C>G		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes AF: 0.000928 AC: 141 AN: 151960 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000990

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000262

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000284

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00137

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00107 AC: 61 AN: 56886 Hom.: 1 Cov.: 3 AF XY: 0.00118 AC XY: 35 AN XY: 29656

Gnomad4 AFR exome AF: 0.000663

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.000603

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.000421

Gnomad4 NFE exome AF: 0.00137

Gnomad4 OTH exome AF: 0.000572

GnomAD4 genome AF: 0.000927 AC: 141 AN: 152070 Hom.: 0 Cov.: 32 AF XY: 0.000861 AC XY: 64 AN XY: 74340

Gnomad4 AFR AF: 0.000987

Gnomad4 AMR AF: 0.000262

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.000284

Gnomad4 NFE AF: 0.00137

Gnomad4 OTH AF: 0.00

Bravo AF: 0.000975

Asia WGS AF: 0.000290 AC: 1 AN: 3458

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Sorsby fundus dystrophy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.78
CADD	Benign	4.8
DANN	Benign	0.73

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: rs1001328821; hg19: chr22-33197714;