16-30699243-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP3_Moderate

The NM_006662.3(SRCAP):c.-284+1G>T variant causes a splice donor 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SRCAP NM_006662.3 splice_donor
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.733

Genes affected

SRCAP (HGNC:16974): (Snf2 related CREBBP activator protein) This gene encodes the core catalytic component of the multiprotein chromatin-remodeling SRCAP complex. The encoded protein is an ATPase that is necessary for the incorporation of the histone variant H2A.Z into nucleosomes. It can function as a transcriptional activator in Notch-mediated, CREB-mediated and steroid receptor-mediated transcription. Mutations in this gene cause Floating-Harbor syndrome, a rare disorder characterized by short stature, language deficits and dysmorphic facial features. [provided by RefSeq, Feb 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.0073248735 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SRCAP	NM_006662.3	c.-284+1G>T		splice_donor_variant		ENST00000262518.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SRCAP	ENST00000262518.9	c.-284+1G>T		splice_donor_variant		2	NM_006662.3	P1
SRCAP	ENST00000411466.7	c.-283-665G>T		intron_variant		3		P1
SRCAP	ENST00000706321.1	c.-284+482G>T		intron_variant				P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental delay, hypotonia, musculoskeletal defects, and behavioral abnormalities Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory of genome editing, Research Centre for Medical Genetics

Sep 20, 2023

The variant was inherited from the mosaic mother. The variant is absent in population databases and is located at a consensus splice site. However, the variant is located in a transcript that is low expressed in all tissues. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
Cadd	Benign	19
Dann	Benign	0.67

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.73
SpliceAI score (max)		0.73		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.73		Position offset: -1

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-30710564;