8-96145173-T-C

Position:

• chr8-96145173-T-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001001557.4(GDF6):​c.758A>G​(p.Gln253Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000193 in 1,499,448 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q253L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000021 (0 hom.)
• Consequence: GDF6 NM_001001557.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.280

Genes affected

GDF6 (HGNC:4221): (growth differentiation factor 6) This gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins. Ligands of this family bind various TGF-beta receptors leading to recruitment and activation of SMAD family transcription factors that regulate gene expression. The encoded preproprotein is proteolytically processed to generate each subunit of the disulfide-linked homodimer. This protein is required for normal formation of some bones and joints in the limbs, skull, and axial skeleton. Mutations in this gene are associated with Klippel-Feil syndrome, microphthalmia, and Leber congenital amaurosis. [provided by RefSeq, Sep 2016]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.16309747).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GDF6	NM_001001557.4	c.758A>G	p.Gln253Arg	missense_variant	2/2	ENST00000287020.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GDF6	ENST00000287020.7	c.758A>G	p.Gln253Arg	missense_variant	2/2	1	NM_001001557.4	P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152084 Hom.: 0 Cov.: 32

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000208 AC: 28 AN: 1347364 Hom.: 0 Cov.: 31 AF XY: 0.0000166 AC XY: 11 AN XY: 664470

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000424

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000254

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152084 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74280

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Klippel-Feil syndrome 1, autosomal dominant;C2751307:Isolated microphthalmia 4;C3150968:Microphthalmia, isolated, with coloboma 6;C3715164:Leber congenital amaurosis 17 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 04, 2020

This sequence change replaces glutamine with arginine at codon 253 of the GDF6 protein (p.Gln253Arg). The glutamine residue is moderately conserved and there is a small physicochemical difference between glutamine and arginine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This variant has not been reported in the literature in individuals with GDF6-related conditions. 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. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.067
BayesDel_addAF	Benign	-0.16	T
BayesDel_noAF	Benign	-0.47
CADD	Benign	14
DANN	Benign	0.62
DEOGEN2	Benign	0.35	T;T
Eigen	Benign	-0.62
Eigen_PC	Benign	-0.56
FATHMM_MKL	Benign	0.16	N
LIST_S2	Benign	0.47	T;T
M_CAP	Pathogenic	0.30	D
MetaRNN	Benign	0.16	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	L;.
MutationTaster	Benign	1.0	N
PrimateAI	Pathogenic	0.84	D
PROVEAN	Benign	-0.75	N;.
REVEL	Benign	0.032
Sift	Benign	0.57	T;.
Sift4G	Benign	0.75	T;T
Polyphen		0.095	B;.
Vest4		0.11
MutPred		0.34		Gain of solvent accessibility (P = 0.0411);Gain of solvent accessibility (P = 0.0411);
MVP		0.60
MPC		0.93
ClinPred		0.076	T
GERP RS		-0.55
Varity_R		0.055
gMVP		0.25

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

Publications

LitVar

Other links and lift over

dbSNP: rs121909355; hg19: chr8-97157401;