chr16-20737872-G-C

Position:

• chr16-20737872-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_017736.5(THUMPD1):​c.491C>G​(p.Pro164Arg) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P164S) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: THUMPD1 NM_017736.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.42

Genes affected

THUMPD1 (HGNC:23807): (THUMP domain containing 1) Enables RNA binding activity. Predicted to be involved in tRNA modification. Predicted to be located in nucleoplasm. [provided by Alliance of Genome Resources, Apr 2022]

ACSM3 (HGNC:10522): (acyl-CoA synthetase medium chain family member 3) Enables butyrate-CoA ligase activity. Predicted to be involved in acyl-CoA metabolic process and fatty acid biosynthetic process. Located in mitochondrion. Implicated in IgA glomerulonephritis. Biomarker of ulcerative colitis. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-20737873-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1333100.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.978

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
THUMPD1	NM_017736.5	c.491C>G	p.Pro164Arg	missense_variant	3/4	ENST00000396083.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
THUMPD1	ENST00000396083.7	c.491C>G	p.Pro164Arg	missense_variant	3/4	1	NM_017736.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder with speech delay and variable ocular anomalies Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neuberg Centre For Genomic Medicine, NCGM

May 20, 2023

The observed missense c.491C>G(p.Pro164Arg) variant in THUMPD1 gene has not been reported previously as a pathogenic variant nor a benign variant, to our knowledge. The p.Pro164Arg variant is absent in gnomAD Exomes. This variant has not been submitted to the ClinVar database. Multiple lines of computational evidences (Polyphen - Probably damaging, SIFT - Damaging and MutationTaster - Disease causing) predict a damaging effect on protein structure and function for this variant. The reference amino acid is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. The amino acid Pro at position 164 is changed to a Arg changing protein sequence and it might alter its composition and physico-chemical properties. Another missense variant [c.490C>T (p.Pro164Ser)] on the same residue of this gene has previously been reported to be disease causing (Broly M, et al., 2022), suggesting that this residue might be of clinical significance. However, additional functional studies will be required to prove the pathogenicity of p.Pro164Arg variant. For these reasons, this variant has been classified as a Variant of Uncertain Significance (VUS). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.58	D;D
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.92	.;D
M_CAP	Pathogenic	0.40	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.3	M;M
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-8.7	D;D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.93
MutPred		0.87		Gain of MoRF binding (P = 0.0031);Gain of MoRF binding (P = 0.0031);
MVP		1.0
MPC		0.75
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.90
gMVP		0.93

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-20749194;