17-46066604-C-G

Variant names:

• chr17-46066604-C-G
• rs1057520691
• NM_015443.4:c.1781G>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_015443.4(KANSL1):​c.1781G>C​(p.Arg594Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R594H) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: KANSL1 NM_015443.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.43
• Publications: 0 publications found

Genes affected

KANSL1 (HGNC:24565): (KAT8 regulatory NSL complex subunit 1) This gene encodes a nuclear protein that is a subunit of two protein complexes involved with histone acetylation, the MLL1 complex and the NSL1 complex. The encoded protein has been implicated in a variety of cellular processes including enhancer regulation, cell proliferation, and mitosis. Mutations in this gene are associated with Koolen-de Vries Syndrome. [provided by RefSeq, May 2022]

KANSL1 Gene-Disease associations (from GenCC):

• Koolen-de Vries syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), ClinGen
• Koolen-de Vries syndrome due to a point mutation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 14 uncertain in NM_015443.4
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KANSL1	NM_015443.4	c.1781G>C	p.Arg594Pro	missense_variant	Exon 6 of 15	ENST00000432791.7	NP_056258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KANSL1	ENST00000432791.7	c.1781G>C	p.Arg594Pro	missense_variant	Exon 6 of 15	1	NM_015443.4	ENSP00000387393.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Koolen-de Vries syndrome Uncertain:1

Dec 02, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 536296). This variant has not been reported in the literature in individuals affected with KANSL1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 594 of the KANSL1 protein (p.Arg594Pro). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KANSL1 protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	29
DANN	Uncertain	1.0
Eigen	Pathogenic	0.71
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.96	.;.;.;.;D;D;D;D;D;D
M_CAP	Benign	0.073	D
MetaRNN	Uncertain	0.72	D;D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.65	T
PhyloP100		5.4
PrimateAI	Uncertain	0.76	T
PROVEAN	Pathogenic	-6.6	D;.;.;.;.;D;.;.;.;.
REVEL	Uncertain	0.37
Sift	Pathogenic	0.0	D;.;.;.;.;D;.;.;.;.
Sift4G	Pathogenic	0.0	D;D;D;.;D;D;.;.;.;.
Vest4		0.95
MutPred		0.46		Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);Loss of MoRF binding (P = 0.0062);.;Loss of MoRF binding (P = 0.0062);
MVP		0.57
MPC		1.6
ClinPred		0.99	D
GERP RS		4.9
gMVP		0.79
Mutation Taster		=60/40	polymorphism

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

Other links and lift over

dbSNP: rs1057520691; hg19: chr17-44143970;