17-7845870-A-G

Variant names:

• chr17-7845870-A-G
• rs2078522713
• NM_001348716.2:c.138-2A>G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PVS1_Moderate PM2 PP5

The NM_001348716.2(KDM6B):​c.138-2A>G variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: KDM6B NM_001348716.2 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 6.54

Genes affected

KDM6B (HGNC:29012): (lysine demethylase 6B) The protein encoded by this gene is a lysine-specific demethylase that specifically demethylates di- or tri-methylated lysine 27 of histone H3 (H3K27me2 or H3K27me3). H3K27 trimethylation is a repressive epigenetic mark controlling chromatin organization and gene silencing. This protein can also demethylate non-histone proteins such as retinoblastoma protein. Through its demethylation actvity this gene influences cellular differentiation and development, tumorigenesis, inflammatory diseases, and neurodegenerative diseases. This protein has two classical nuclear localization signals at its N-terminus. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Feb 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.020072993 fraction of the gene. Cryptic splice site detected, with MaxEntScore 6.8, offset of -17, new splice context is: ctttttgccgtatataacAGact. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-7845870-A-G is Pathogenic according to our data. Variant chr17-7845870-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1704447.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KDM6B	NM_001348716.2	c.138-2A>G		splice_acceptor_variant, intron_variant	Intron 5 of 23	ENST00000448097.7	NP_001335645.1
KDM6B	NM_001080424.2	c.138-2A>G		splice_acceptor_variant, intron_variant	Intron 4 of 21		NP_001073893.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KDM6B	ENST00000448097.7	c.138-2A>G		splice_acceptor_variant, intron_variant	Intron 5 of 23	5	NM_001348716.2	ENSP00000412513.2
KDM6B	ENST00000254846.9	c.138-2A>G		splice_acceptor_variant, intron_variant	Intron 4 of 21	1		ENSP00000254846.5
KDM6B	ENST00000570632.1	c.138-2A>G		splice_acceptor_variant, intron_variant	Intron 3 of 8	5		ENSP00000458445.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1460914 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726840

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Neurodevelopmental disorder with coarse facies and mild distal skeletal abnormalities Pathogenic:1

Sep 09, 2022

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.94	D
GERP RS		3.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.46		Position offset: 10
DS_AL_spliceai		0.99		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs2078522713; hg19: chr17-7749188;