22-37303359-G-T

Variant names:

• chr22-37303359-G-T
• rs774848140
• NM_013385.5:c.653G>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_013385.5(CYTH4):​c.653G>T​(p.Arg218Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,762 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R218H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CYTH4 NM_013385.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.15
• Publications: 0 publications found

Genes affected

CYTH4 (HGNC:9505): (cytohesin 4) This gene encodes a member of the PSCD family of proteins, which have an N-terminal coiled-coil motif, a central Sec7 domain, and a C-terminal pleckstrin homology (PH) domain. The coiled-coil motif is involved in homodimerization, the Sec7 domain contains guanine-nucleotide exchange protein (GEP) activity, and the PH domain interacts with phospholipids and is responsible for association of PSCDs with membranes. Members of this family function as GEPs for ADP-ribosylation factors (ARFs), which are guanine nucleotide-binding proteins involved in vesicular trafficking pathways. This protein exhibits GEP activity in vitro with ARF1 and ARF5, but is inactive with ARF6. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Dec 2015]

ENSG00000298470 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.93

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_013385.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYTH4	NM_013385.5	MANE Select	c.653G>T	p.Arg218Leu	missense	Exon 8 of 13	NP_037517.1	Q9UIA0
	CYTH4	NM_001318024.2		c.482G>T	p.Arg161Leu	missense	Exon 8 of 13	NP_001304953.1	B4E2V8

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYTH4	ENST00000248901.11	TSL:1 MANE Select	c.653G>T	p.Arg218Leu	missense	Exon 8 of 13	ENSP00000248901.6	Q9UIA0
	CYTH4	ENST00000868416.1		c.650G>T	p.Arg217Leu	missense	Exon 8 of 13	ENSP00000538475.1
	CYTH4	ENST00000462927.5	TSL:2	n.698G>T		non_coding_transcript_exon	Exon 8 of 13

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461762 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727202

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44684

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111972

Other (OTH) AF: 0.00 AC: 0 AN: 60388

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0296732), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.36
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.19	T
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Uncertain	0.41	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		8.2
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-6.8	D
REVEL	Uncertain	0.52
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.011	D
Polyphen		0.83	P
Vest4		0.92
MutPred		0.79		Loss of disorder (P = 0.0314)
MVP		0.66
MPC		0.94
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.81
gMVP		0.88
Mutation Taster		=63/37	polymorphism

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

Other links and lift over

dbSNP: rs774848140; hg19: chr22-37699400;