NM_015443.4:c.808_809delCT

Variant names:

• chr17-46171334-CAG-C
• rs551541795
• NM_015443.4:c.808_809delCT

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PVS1 PP5

The NM_015443.4(KANSL1):​c.808_809delCT​(p.Leu270ValfsTer11) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,614,018 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L270L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 35)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: KANSL1 NM_015443.4 frameshift
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:6 U:3
• Conservation: PhyloP100: 2.03
• Publications: 3 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, Labcorp Genetics (formerly Invitae), ClinGen, G2P
• Koolen-de Vries syndrome due to a point mutation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 17-46171334-CAG-C is Pathogenic according to our data. Variant chr17-46171334-CAG-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 468412.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015443.4. 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
	KANSL1	NM_015443.4	MANE Select	c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 2 of 15	NP_056258.1	Q7Z3B3-1
	KANSL1	NM_001193466.2		c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 2 of 15	NP_001180395.1	Q7Z3B3-1
	KANSL1	NM_001379198.1		c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 3 of 16	NP_001366127.1	Q7Z3B3-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KANSL1	ENST00000432791.7	TSL:1 MANE Select	c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 2 of 15	ENSP00000387393.3	Q7Z3B3-1
	KANSL1	ENST00000262419.10	TSL:1	c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 2 of 15	ENSP00000262419.6	Q7Z3B3-1
	KANSL1	ENST00000918919.1		c.808_809delCT	p.Leu270ValfsTer11	frameshift	Exon 2 of 16	ENSP00000588978.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152140 Hom.: 0 Cov.: 35

Gnomad AFR AF: 0.00

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: 0.00

GnomAD2 exomes AF: 0.0000239 AC: 6 AN: 251458 AF XY: 0.0000368

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS 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: 0.0000164 AC: 24 AN: 1461878 Hom.: 0 AF XY: 0.0000206 AC XY: 15 AN XY: 727244

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

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000464 AC: 4 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.0000153 AC: 17 AN: 1111998

Other (OTH) AF: 0.0000331 AC: 2 AN: 60394

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152140 Hom.: 0 Cov.: 35 AF XY: 0.0000135 AC XY: 1 AN XY: 74322

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

African (AFR) AF: 0.00 AC: 0 AN: 41410

American (AMR) AF: 0.00 AC: 0 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10600

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000843 Hom.: 0

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
3	2	-	Koolen-de Vries syndrome (5)
1	-	-	Inborn genetic diseases (1)
1	-	-	KANSL1-related disorder (1)
1	-	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.0
Mutation Taster		=0/200	disease causing (ClinVar)

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: rs551541795; hg19: chr17-44248700;