17-41255614-A-G

Position:

• chr17-41255614-A-G

Variant summary

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

The NM_030975.2(KRTAP9-9):​c.229A>G​(p.Ser77Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/18 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 31)
• Consequence: KRTAP9-9 NM_030975.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -2.74

Genes affected

KRTAP9-9 (HGNC:16773): (keratin associated protein 9-9) This protein is a member of the keratin-associated protein (KAP) family. The KAP proteins form a matrix of keratin intermediate filaments which contribute to the structure of hair fibers. KAP family members appear to have unique, family-specific amino- and carboxyl-terminal regions and are subdivided into three multi-gene families according to amino acid composition: the high sulfur, the ultrahigh sulfur, and the high tyrosine/glycine KAPs. This protein is a member of the ultrahigh sulfur KAP family and the gene is localized to a cluster of KAPs at 17q12-q21. Alternative haplotypes of this gene are represented in the GRCh38 reference genome assembly. [provided by RefSeq, Dec 2015]

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=0.048156917).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KRTAP9-9	NM_030975.2	c.229A>G	p.Ser77Gly	missense_variant	1/1		NP_112237.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KRTAP9-9	ENST00000394008.1	c.229A>G	p.Ser77Gly	missense_variant	1/1	6		ENSP00000377576.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 31

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

Oct 29, 2024

The c.229A>G (p.S77G) alteration is located in exon 1 (coding exon 1) of the KRTAP9-9 gene. This alteration results from a A to G substitution at nucleotide position 229, causing the serine (S) at amino acid position 77 to be replaced by a glycine (G). 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
BayesDel_addAF	Benign	-0.38	T
BayesDel_noAF	Benign	-0.78
CADD	Benign	2.3
DANN	Benign	0.89
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.0059	N
M_CAP	Benign	0.0028	T
MetaRNN	Benign	0.048	T
MetaSVM	Benign	-0.91	T
PrimateAI	Benign	0.20	T
PROVEAN	Benign	-2.0	N
REVEL	Benign	0.027
Sift	Benign	0.30	T
Sift4G	Benign	0.37	T
Vest4		0.15
MutPred		0.34		Gain of relative solvent accessibility (P = 0.0166);
MVP		0.014
MPC		0.033
ClinPred		0.056	T
GERP RS		-4.3
gMVP		0.033

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1489136034; hg19: chr17-39411866;