rs200347935

Positions:

• chr22-36876028-G-A
• chr22-36876028-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP3_Moderate

The NM_000631.5(NCF4):​c.759-1G>A variant causes a splice acceptor change. The variant allele was found at a frequency of 0.00000137 in 1,461,012 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 1/1 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NCF4 NM_000631.5 splice_acceptor
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.26

Genes affected

NCF4 (HGNC:7662): (neutrophil cytosolic factor 4) The protein encoded by this gene is a cytosolic regulatory component of the superoxide-producing phagocyte NADPH-oxidase, a multicomponent enzyme system important for host defense. This protein is preferentially expressed in cells of myeloid lineage. It interacts primarily with neutrophil cytosolic factor 2 (NCF2/p67-phox) to form a complex with neutrophil cytosolic factor 1 (NCF1/p47-phox), which further interacts with the small G protein RAC1 and translocates to the membrane upon cell stimulation. This complex then activates flavocytochrome b, the membrane-integrated catalytic core of the enzyme system. The PX domain of this protein can bind phospholipid products of the PI(3) kinase, which suggests its role in PI(3) kinase-mediated signaling events. The phosphorylation of this protein was found to negatively regulate the enzyme activity. Alternatively spliced transcript variants encoding distinct isoforms have been observed. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.033836544 fraction of the gene. Cryptic splice site detected, with MaxEntScore 4.9, offset of 1, new splice context is: cagcctgtcacccccttaAGgac. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NCF4	NM_000631.5	c.759-1G>A		splice_acceptor_variant		ENST00000248899.11
NCF4	XM_047441384.1	c.933-1G>A		splice_acceptor_variant
NCF4	XM_047441385.1	c.903-1G>A		splice_acceptor_variant
NCF4	NM_013416.4	c.1003G>A	p.Gly335Arg	missense_variant	8/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NCF4	ENST00000248899.11	c.759-1G>A		splice_acceptor_variant		1	NM_000631.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461012 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 726626

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Benign	-0.32
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.95	D
M_CAP	Uncertain	0.12	D
MutationTaster	Benign	1.0	D;N
ClinPred		0.98	D
GERP RS		5.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.86		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.45		Position offset: 2
DS_AL_spliceai		0.86		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs200347935; hg19: chr22-37272070;