chr16-90022722-A-G

Position:

• chr16-90022722-A-G

Variant summary

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

The NM_001481.3(GAS8):​c.1A>G​(p.Met1?) variant causes a start lost, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000237 in 1,263,394 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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: 33)
  • Exomes 𝑓: 0.0000024 (0 hom.)
• Consequence: GAS8 NM_001481.3 start_lost, splice_region
• Scores: Splicing: ADA: 0.002096
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.48

Genes affected

GAS8 (HGNC:4166): (growth arrest specific 8) This gene includes 11 exons spanning 25 kb and maps to a region of chromosome 16 that is sometimes deleted in breast and prostrate cancer. The second intron contains an apparently intronless gene, C16orf3, that is transcribed in the opposite orientation. This gene is a putative tumor suppressor gene. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GAS8	NM_001481.3	c.1A>G	p.Met1?	start_lost, splice_region_variant	1/11	ENST00000268699.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GAS8	ENST00000268699.9	c.1A>G	p.Met1?	start_lost, splice_region_variant	1/11	1	NM_001481.3	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000237 AC: 3 AN: 1263394 Hom.: 0 Cov.: 31 AF XY: 0.00000324 AC XY: 2 AN XY: 616714

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: 0.00000297

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia 33 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 22, 2021

This sequence change affects the initiator methionine of the GAS8 mRNA. The next in-frame methionine is located at codon 26. 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 affected with GAS8-related conditions. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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
BayesDel_addAF	Uncertain	0.073	D
BayesDel_noAF	Benign	-0.13
CADD	Benign	22
DANN	Benign	0.69
DEOGEN2	Benign	0.049	T
Eigen	Benign	0.085
Eigen_PC	Benign	-0.0023
FATHMM_MKL	Benign	0.63	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.76	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Benign	-1.1	T
MutationTaster	Benign	1.0	D;D
PROVEAN	Benign	-1.8	N
REVEL	Benign	0.23
Sift	Benign	0.037	D
Sift4G	Uncertain	0.0090	D
Polyphen		0.014	B
Vest4		0.84
MutPred		0.99		Loss of glycosylation at K4 (P = 0.166);
MVP		0.48
ClinPred		0.14	T
GERP RS		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.38
gMVP		0.38

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0021
dbscSNV1_RF	Benign	0.078
SpliceAI score (max)		0.010		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: rs1057484078; hg19: chr16-90089130;