14-60509489-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP3 BS1_Supporting

The NM_007374.3(SIX6):c.91G>C(p.Gly31Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000025 in 1,602,368 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SIX6 NM_007374.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

Genes affected

SIX6 (HGNC:10892): (SIX homeobox 6) The protein encoded by this gene is a homeobox protein that is similar to the Drosophila 'sine oculis' gene product. This gene is found in a cluster of related genes on chromosome 14 and is thought to be involved in eye development. Defects in this gene are a cause of isolated microphthalmia with cataract type 2 (MCOPCT2). [provided by RefSeq, Jul 2008]

C14orf39 (HGNC:19849): (chromosome 14 open reading frame 39) Predicted to be involved in gamete generation and meiosis I. Predicted to be located in chromosome. Predicted to be active in central element. Implicated in primary ovarian insufficiency 18 and spermatogenic failure 52. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.788
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0000197 (3/152216) while in subpopulation AFR AF= 0.0000723 (3/41466). AF 95% confidence interval is 0.0000192. There are 0 homozygotes in gnomad4. There are 1 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SIX6	NM_007374.3	c.91G>C	p.Gly31Arg	missense_variant	1/2	ENST00000327720.6
C14orf39	XM_047431324.1	c.-144+5906C>G		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SIX6	ENST00000327720.6	c.91G>C	p.Gly31Arg	missense_variant	1/2	1	NM_007374.3	P1
C14orf39	ENST00000556799.1	c.-144+5906C>G		intron_variant		4

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152216 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000723

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.90e-7 AC: 1 AN: 1450152 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 721850

Gnomad4 AFR exome AF: 0.0000299

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 AF: 0.0000197 AC: 3 AN: 152216 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74364

Gnomad4 AFR AF: 0.0000723

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: 0.00

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

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 22, 2022

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. This variant has not been reported in the literature in individuals affected with SIX6-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 31 of the SIX6 protein (p.Gly31Arg). 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	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
Cadd	Pathogenic	30
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.61	D
Eigen	Uncertain	0.66
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.35	D
MetaRNN	Pathogenic	0.79	D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Uncertain	2.4	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-4.8	D
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0070	D
Sift4G	Uncertain	0.034	D
Polyphen		0.84	P
Vest4		0.83
MutPred		0.41		Gain of solvent accessibility (P = 0.0674);
MVP		0.92
MPC		1.2
ClinPred		0.99	D
GERP RS		5.7
Varity_R		0.84
gMVP		0.90

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: rs1296136036; hg19: chr14-60976207;