chr9-441905-C-T

Variant names:

• chr9-441905-C-T
• rs775544616
• NM_203447.4:c.5386C>T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_203447.4(DOCK8):​c.5386C>T​(p.Arg1796*) variant causes a stop gained change. The variant allele was found at a frequency of 0.000000684 in 1,461,836 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DOCK8 NM_203447.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 3.92

Genes affected

DOCK8 (HGNC:19191): (dedicator of cytokinesis 8) This gene encodes a member of the DOCK180 family of guanine nucleotide exchange factors. Guanine nucleotide exchange factors interact with Rho GTPases and are components of intracellular signaling networks. Mutations in this gene result in the autosomal recessive form of the hyper-IgE syndrome. Alternatively spliced transcript variants encoding different isoforms have been described.[provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-441905-C-T is Pathogenic according to our data. Variant chr9-441905-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 576864.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DOCK8	NM_203447.4	c.5386C>T	p.Arg1796*	stop_gained	Exon 42 of 48	ENST00000432829.7	NP_982272.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DOCK8	ENST00000432829.7	c.5386C>T	p.Arg1796*	stop_gained	Exon 42 of 48	1	NM_203447.4	ENSP00000394888.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251446 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135896

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461836 Hom.: 0 Cov.: 54 AF XY: 0.00000138 AC XY: 1 AN XY: 727216

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Combined immunodeficiency due to DOCK8 deficiency Pathogenic:1

Jun 01, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Pathogenic:1

Oct 06, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg1796*) in the DOCK8 gene. It is expected to result in an absent or disrupted protein product. This variant is present in population databases (rs775544616, ExAC 0.01%). This homozygous variant has been reported in the germline of several individuals affected with DOCK8 deficiency who exhibited mutation reversion due to somatic repair in lymphocytes (PMID: 24797421). This variant is also referred to as c.5182C>T (p.R1728X) in the literature. Loss-of-function variants in DOCK8 are known to be pathogenic (PMID: 14722525, 19776401). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	48
DANN	Uncertain	1.0
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Uncertain	0.95	D
Vest4		0.86
GERP RS		5.7

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: rs775544616; hg19: chr9-441905;