4-39407023-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_175737.4(KLB):c.74G>A(p.Arg25His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000204 in 1,613,972 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000020 (0 hom.)
• Consequence: KLB NM_175737.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.128

Genes affected

KLB (HGNC:15527): (klotho beta) Enables fibroblast growth factor binding activity and fibroblast growth factor receptor binding activity. Predicted to be involved in fibroblast growth factor receptor signaling pathway. Predicted to act upstream of or within positive regulation of MAPKKK cascade by fibroblast growth factor receptor signaling pathway and positive regulation of cell population proliferation. Predicted to be located in plasma membrane. Predicted to be active in endoplasmic reticulum. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.052677363).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KLB	NM_175737.4	c.74G>A	p.Arg25His	missense_variant	1/5	ENST00000257408.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KLB	ENST00000257408.5	c.74G>A	p.Arg25His	missense_variant	1/5	1	NM_175737.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152152 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 251398 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135876

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000198 AC: 29 AN: 1461820 Hom.: 0 Cov.: 31 AF XY: 0.0000165 AC XY: 12 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000112

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: 0.0000207

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152152 Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3 AN XY: 74328

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.000478

Alfa AF: 0.0000540 Hom.: 0

Bravo AF: 0.0000189

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.000109

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 17, 2023

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 25 of the KLB protein (p.Arg25His). This variant is present in population databases (rs755268107, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with KLB-related conditions. ClinVar contains an entry for this variant (Variation ID: 1475038). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.079
BayesDel_addAF	Benign	-0.48	T
BayesDel_noAF	Benign	-0.73
Cadd	Benign	9.9
Dann	Benign	0.95
DEOGEN2	Benign	0.034	T
Eigen	Benign	-0.77
Eigen_PC	Benign	-0.69
FATHMM_MKL	Benign	0.11	N
LIST_S2	Benign	0.59	T
M_CAP	Benign	0.0042	T
MetaRNN	Benign	0.053	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.19	T
PROVEAN	Benign	-0.65	N
REVEL	Benign	0.030
Sift	Benign	0.33	T
Sift4G	Benign	0.27	T
Polyphen		0.0040	B
Vest4		0.052
MutPred		0.22		Gain of glycosylation at T24 (P = 0.0235);
MVP		0.35
MPC		0.72
ClinPred		0.023	T
GERP RS		2.4
Varity_R		0.031
gMVP		0.25

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: rs755268107; hg19: chr4-39408643;