8-144511789-G-A

Position:

• chr8-144511789-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_004260.4(RECQL4):​c.3394C>T​(p.Leu1132Phe) variant causes a missense, splice region 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. 12/16 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 34)
• Consequence: RECQL4 NM_004260.4 missense, splice_region
• Scores: Splicing: ADA: 0.00009513
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.568

Genes affected

RECQL4 (HGNC:9949): (RecQ like helicase 4) The protein encoded by this gene is a DNA helicase that belongs to the RecQ helicase family. DNA helicases unwind double-stranded DNA into single-stranded DNAs and may modulate chromosome segregation. This gene is predominantly expressed in thymus and testis. Mutations in this gene are associated with Rothmund-Thomson, RAPADILINO and Baller-Gerold syndromes. [provided by RefSeq, Jan 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.29189014).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RECQL4	NM_004260.4	c.3394C>T	p.Leu1132Phe	missense_variant, splice_region_variant	20/21	ENST00000617875.6	NP_004251.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RECQL4	ENST00000617875.6	c.3394C>T	p.Leu1132Phe	missense_variant, splice_region_variant	20/21	1	NM_004260.4	ENSP00000482313	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Baller-Gerold syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 16, 2017

Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing, but this prediction has not been confirmed by published transcriptional studies. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with RECQL4-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with phenylalanine at codon 1132 of the RECQL4 protein (p.Leu1132Phe). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and phenylalanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.10	T
BayesDel_noAF	Benign	-0.39
CADD	Benign	18
DANN	Benign	0.86
DEOGEN2	Benign	0.031	T;T;T
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.61	T;T;T
M_CAP	Benign	0.043	D
MetaRNN	Benign	0.21	T;T;T
MutationAssessor	Uncertain	2.8	.;M;.
PrimateAI	Benign	0.44	T
Sift4G	Benign	0.26	T;T;T
Polyphen		0.048	.;B;.
Vest4		0.48
MVP		0.45
GERP RS		1.9
Varity_R		0.050
gMVP		0.49

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000095
dbscSNV1_RF	Benign	0.0
SpliceAI score (max)		0.18		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: rs1554895894; hg19: chr8-145737172;