rs541533278

chr1-243286369-T-C

Variant summary

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

The NM_006642.5(SDCCAG8):c.518T>C(p.Leu173Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000039 in 1,614,076 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. L173L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000040 (1 hom.)
• Consequence: SDCCAG8 NM_006642.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 1.74

Genes affected

SDCCAG8 (HGNC:10671): (SHH signaling and ciliogenesis regulator SDCCAG8) This gene encodes a centrosome associated protein. This protein may be involved in organizing the centrosome during interphase and mitosis. Mutations in this gene are associated with retinal-renal ciliopathy. [provided by RefSeq, Oct 2010]

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
SDCCAG8	NM_006642.5	c.518T>C	p.Leu173Pro	missense_variant	5/18	ENST00000366541.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SDCCAG8	ENST00000366541.8	c.518T>C	p.Leu173Pro	missense_variant	5/18	1	NM_006642.5	P1

Frequencies

GnomAD3 genomes AF: 0.0000328 AC: 5 AN: 152222 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.0000588

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000716 AC: 18 AN: 251268 Hom.: 1 AF XY: 0.0000810 AC XY: 11 AN XY: 135816

Gnomad AFR exome AF: 0.0000617

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.0000992

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000123

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000397 AC: 58 AN: 1461736 Hom.: 1 Cov.: 31 AF XY: 0.0000358 AC XY: 26 AN XY: 727182

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000477

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000328 AC: 5 AN: 152340 Hom.: 0 Cov.: 32 AF XY: 0.0000403 AC XY: 3 AN XY: 74492

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000588

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000302

ExAC AF: 0.0000906 AC: 11

EpiCase AF: 0.0000545

EpiControl AF: 0.000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Senior-Loken syndrome 7;C3889474:Bardet-Biedl syndrome 16 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Feb 17, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Oct 27, 2021	This sequence change replaces leucine, a(n) neutral and non-polar amino acid, with proline, a(n) neutral and non-polar amino acid, at codon 173 of the SDCCAG8 protein (p.Leu173Pro). This variant is present in population databases (rs541533278, gnomAD 0.01%), including at least one homozygous and/or hemizygous individual. This variant has not been reported in the literature in individuals affected with SDCCAG8-related conditions. ClinVar contains an entry for this variant (Variation ID: 541793). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Senior-Loken syndrome 7 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Bardet-Biedl syndrome 16 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.35
Cadd	Uncertain	24
Dann	Uncertain	0.99
DEOGEN2	Benign	0.25	T
Eigen	Benign	0.11
Eigen_PC	Benign	0.12
FATHMM_MKL	Uncertain	0.88	D
M_CAP	Benign	0.021	T
MetaRNN	Uncertain	0.55	D
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.3	L
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Benign	0.41	T
PROVEAN	Uncertain	-3.3	D
REVEL	Benign	0.078
Sift	Uncertain	0.0020	D
Sift4G	Benign	0.062	T
Polyphen		0.98	D
Vest4		0.73
MutPred		0.43		Gain of glycosylation at L173 (P = 0.0257);
MVP		0.28
MPC		0.24
ClinPred		0.22	T
GERP RS		3.3
Varity_R		0.72
gMVP		0.41

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: rs541533278; hg19: chr1-243449671;