16-1227472-A-C

Position:

• chr16-1227472-A-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000611196.4(TPSB2):​c.*111-3T>G variant causes a splice region, splice polypyrimidine tract, intron, NMD transcript 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: 35)
• Consequence: TPSB2 ENST00000611196.4 splice_region, splice_polypyrimidine_tract, intron, NMD_transcript
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.117

Genes affected

TPSB2 (HGNC:14120): (tryptase beta 2) Tryptases comprise a family of trypsin-like serine proteases, the peptidase family S1. Tryptases are enzymatically active only as heparin-stabilized tetramers, and they are resistant to all known endogenous proteinase inhibitors. Several tryptase genes are clustered on chromosome 16p13.3. These genes are characterized by several distinct features. They have a highly conserved 3' UTR and contain tandem repeat sequences at the 5' flank and 3' UTR which are thought to play a role in regulation of the mRNA stability. These genes have an intron immediately upstream of the initiator Met codon, which separates the site of transcription initiation from protein coding sequence. This feature is characteristic of tryptases but is unusual in other genes. The alleles of this gene exhibit an unusual amount of sequence variation, such that the alleles were once thought to represent two separate genes, beta II and beta III. Beta tryptases appear to be the main isoenzymes expressed in mast cells, whereas in basophils, alpha-tryptases predominate. Tryptases have been implicated as mediators in the pathogenesis of asthma and other allergic and inflammatory disorders. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.93).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TPSB2	ENST00000611196.4	c.*111-3T>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant, NMD_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 35

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 35

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.93
CADD	Benign	7.1
DANN	Benign	0.50

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs2745145; hg19: chr16-1277472;