17-5444462-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_020162.4(DHX33):c.1867T>C(p.Cys623Arg) 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 (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DHX33 NM_020162.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.63

Genes affected

DHX33 (HGNC:16718): (DEAH-box helicase 33) This gene encodes a member of the DEAD box protein family. The DEAD box proteins are characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this DEAD box protein family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2010]

C1QBP (HGNC:1243): (complement C1q binding protein) The human complement subcomponent C1q associates with C1r and C1s in order to yield the first component of the serum complement system. The protein encoded by this gene is known to bind to the globular heads of C1q molecules and inhibit C1 activation. This protein has also been identified as the p32 subunit of pre-mRNA splicing factor SF2, as well as a hyaluronic acid-binding protein. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.944

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DHX33	NM_020162.4	c.1867T>C	p.Cys623Arg	missense_variant	12/12	ENST00000225296.8
DHX33	NM_001199699.2	c.1348T>C	p.Cys450Arg	missense_variant	11/11
DHX33	XM_017024877.2	c.583T>C	p.Cys195Arg	missense_variant	8/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DHX33	ENST00000225296.8	c.1867T>C	p.Cys623Arg	missense_variant	12/12	1	NM_020162.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 27, 2024

The c.1867T>C (p.C623R) alteration is located in exon 12 (coding exon 12) of the DHX33 gene. This alteration results from a T to C substitution at nucleotide position 1867, causing the cysteine (C) at amino acid position 623 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.070
Cadd	Pathogenic	28
Dann	Uncertain	1.0
DEOGEN2	Benign	0.27	T;T
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.81	T;T
M_CAP	Benign	0.072	D
MetaRNN	Pathogenic	0.94	D;D
MetaSVM	Benign	-1.0	T
MutationAssessor	Pathogenic	3.9	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-9.4	D;D
REVEL	Uncertain	0.50
Sift	Uncertain	0.0030	D;D
Sift4G	Uncertain	0.0030	D;D
Polyphen		1.0	D;D
Vest4		0.82
MutPred		0.86		Gain of MoRF binding (P = 0.0054);.;
MVP		0.80
MPC		1.2
ClinPred		1.0	D
GERP RS		4.6
Varity_R		0.95
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

LitVar

Other links and lift over

dbSNP: rs1916561769; hg19: chr17-5347782;