chr8-144517051-T-C

Position:

• chr8-144517051-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004260.4(RECQL4):​c.353A>G​(p.Gln118Arg) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000343 in 1,457,046 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/15 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)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: RECQL4 NM_004260.4 missense, splice_region
• Scores: Splicing: ADA: 0.0004116
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.232

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]

RECQL4 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.13029629).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RECQL4	NM_004260.4	c.353A>G	p.Gln118Arg	missense_variant, splice_region_variant	4/21	ENST00000617875.6	NP_004251.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RECQL4	ENST00000617875.6	c.353A>G	p.Gln118Arg	missense_variant, splice_region_variant	4/21	1	NM_004260.4	ENSP00000482313.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000343 AC: 5 AN: 1457046 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 724034

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: 0.00000451

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

TwinsUK AF: 0.00 AC: 0

ALSPAC AF: 0.000259 AC: 1

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

Dec 04, 2020

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 sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Not available"; Align-GVGD: "Class C0". The arginine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. 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 glutamine with arginine at codon 118 of the RECQL4 protein (p.Gln118Arg). The glutamine residue is moderately conserved and there is a small physicochemical difference between glutamine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Benign	0.0059	T
BayesDel_noAF	Benign	-0.23
CADD	Benign	20
DANN	Benign	0.57
DEOGEN2	Benign	0.055	T
FATHMM_MKL	Benign	0.72	D
LIST_S2	Benign	0.50	T
M_CAP	Benign	0.0014	T
MetaRNN	Benign	0.13	T
PrimateAI	Benign	0.44	T
Sift4G	Benign	0.33	T
Polyphen		0.42	B
Vest4		0.18
MVP		0.72
GERP RS		2.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.074
gMVP		0.21

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00041
dbscSNV1_RF	Benign	0.012
SpliceAI score (max)		0.030		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: rs757435100; hg19: chr8-145742435;