22-37701304-A-C

Variant names:

• chr22-37701304-A-C
• rs367660058
• NM_001039141.3:c.-60-2A>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PVS1_Moderate BS1_Supporting

The NM_001039141.3(TRIOBP):​c.-60-2A>C variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000107 in 1,369,224 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00019 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000097 (0 hom.)
• Consequence: TRIOBP NM_001039141.3 splice_acceptor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.40
• Publications: 0 publications found

Genes affected

TRIOBP (HGNC:17009): (TRIO and F-actin binding protein) This gene encodes a protein with an N-terminal pleckstrin homology domain and a C-terminal coiled-coil region. The protein interacts with trio, which is involved with neural tissue development and controlling actin cytoskeleton organization, cell motility and cell growth. The protein also associates with F-actin and stabilizes F-actin structures. Mutations in this gene have been associated with a form of autosomal recessive nonsyndromic deafness. Multiple alternatively spliced transcript variants that would encode different isoforms have been found for this gene, however some transcripts may be subject to nonsense-mediated decay (NMD). [provided by RefSeq, Nov 2008]

TRIOBP Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 28

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), PanelApp Australia
• hearing loss, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet

ENSG00000100101 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.024513947 fraction of the gene. Cryptic splice site detected, with MaxEntScore 5.1, offset of 11, new splice context is: ttttgcccggcctcacatAGacg. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• BS1: Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.00019 (29/152276) while in subpopulation EAS AF = 0.00328 (17/5186). AF 95% confidence interval is 0.00209. There are 0 homozygotes in GnomAd4. There are 12 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TRIOBP	NM_001039141.3	c.-60-2A>C		splice_acceptor_variant, intron_variant	Intron 2 of 23	ENST00000644935.1	NP_001034230.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TRIOBP	ENST00000644935.1	c.-60-2A>C		splice_acceptor_variant, intron_variant	Intron 2 of 23		NM_001039141.3	ENSP00000496394.1
ENSG00000100101	ENST00000455236.4	n.*277-2A>C		splice_acceptor_variant, intron_variant	Intron 8 of 12	5		ENSP00000477208.1
TRIOBP	ENST00000492485.5	n.77-2A>C		splice_acceptor_variant, intron_variant	Intron 1 of 4	1
TRIOBP	ENST00000344404.10	n.-60-2A>C		splice_acceptor_variant, intron_variant	Intron 1 of 21	2		ENSP00000340312.6

Frequencies

GnomAD3 genomes AF: 0.000191 AC: 29 AN: 152158 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000265

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00327

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.000478

GnomAD4 exome AF: 0.0000970 AC: 118 AN: 1216948 Hom.: 0 Cov.: 17 AF XY: 0.0000981 AC XY: 60 AN XY: 611532

African (AFR) AF: 0.000137 AC: 4 AN: 29116

American (AMR) AF: 0.0000275 AC: 1 AN: 36406

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 23990

East Asian (EAS) AF: 0.00183 AC: 69 AN: 37638

South Asian (SAS) AF: 0.0000260 AC: 2 AN: 76856

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50176

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5306

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 905262

Other (OTH) AF: 0.000805 AC: 42 AN: 52198

GnomAD4 genome AF: 0.000190 AC: 29 AN: 152276 Hom.: 0 Cov.: 32 AF XY: 0.000161 AC XY: 12 AN XY: 74472

African (AFR) AF: 0.000265 AC: 11 AN: 41556

American (AMR) AF: 0.00 AC: 0 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00328 AC: 17 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10618

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68018

Other (OTH) AF: 0.000473 AC: 1 AN: 2116

Alfa AF: 0.000214 Hom.: 0

Bravo AF: 0.000264

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Jul 08, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Canonical splice site variant expected to result in aberrant splicing, although in the absence of functional evidence the actual effect of this sequence change is unknown.; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.74
CADD	Benign	19
DANN	Benign	0.75
PhyloP100		1.4

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.79
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.91		Position offset: 13
DS_AL_spliceai		0.99		Position offset: 2

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

Other links and lift over

dbSNP: rs367660058; hg19: chr22-38097311;