X-123614183-T-C

Position:

• chrX-123614183-T-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM2 PP2 BP4_Strong

The NM_001081550.2(THOC2):​c.4318A>G​(p.Ile1440Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000951 in 1,051,520 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 9.5e-7 (0 hom. 0 hem.)
• Consequence: THOC2 NM_001081550.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.625

Genes affected

THOC2 (HGNC:19073): (THO complex subunit 2) The TREX multiprotein complex binds specifically to spliced mRNAs to facilitate mRNA export. The protein encoded by this gene is a member of the THO complex, a subset of the TREX complex. The encoded protein interacts with the THOC1 protein.[provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), THOC2. . Gene score misZ 5.5258 (greater than the threshold 3.09). GenCC has associacion of gene with X-linked intellectual disability-short stature-overweight syndrome.
• BP4: Computational evidence support a benign effect (MetaRNN=0.061397076).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
THOC2	NM_001081550.2	c.4318A>G	p.Ile1440Val	missense_variant	34/39	ENST00000245838.13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
THOC2	ENST00000245838.13	c.4318A>G	p.Ile1440Val	missense_variant	34/39	5	NM_001081550.2	P1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome AF: 9.51e-7 AC: 1 AN: 1051520 Hom.: 0 Cov.: 26 AF XY: 0.00 AC XY: 0 AN XY: 328656

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000227

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

X-linked intellectual disability-short stature-overweight syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Mar 31, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3C. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with intellectual developmental disorder, X-linked 12 (MIM#300957). (I) 0109 - This gene is associated with X-linked recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from isoleucine to valine. (I) 0253 - This variant is hemizygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0504 - Same amino acid change has been observed in placental mammals. (SB) 0603 - Missense variant in a region that is highly intolerant to missense variation (high constraint region in DECIPHER). (SP) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1205 - This variant has been shown to be maternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.062
BayesDel_addAF	Benign	-0.28	T
BayesDel_noAF	Benign	-0.64
CADD	Benign	12
DANN	Benign	0.48
DEOGEN2	Benign	0.025	T;.;.;T;T
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Benign	0.66	T;T;T;.;T
M_CAP	Benign	0.0017	T
MetaRNN	Benign	0.061	T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.34	N;.;.;N;.
MutationTaster	Benign	0.97	N;N;N
PrimateAI	Benign	0.37	T
PROVEAN	Benign	-0.19	N;.;N;N;N
REVEL	Benign	0.035
Sift	Benign	0.41	T;.;T;T;T
Sift4G	Benign	0.90	T;T;T;T;T
Polyphen		0.0010	B;.;.;B;.
Vest4		0.094
MutPred		0.25		Loss of helix (P = 0.0558);.;.;Loss of helix (P = 0.0558);.;
MVP		0.29
MPC		0.66
ClinPred		0.046	T
GERP RS		-0.95
Varity_R		0.037
gMVP		0.030

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-122748034;