8-100165907-T-TA

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_003114.5(SPAG1):c.237dup(p.Pro80ThrfsTer11) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000684 in 1,461,864 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: SPAG1 NM_003114.5 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 4.84

Genes affected

SPAG1 (HGNC:11212): (sperm associated antigen 1) The correlation of anti-sperm antibodies with cases of unexplained infertility implicates a role for these antibodies in blocking fertilization. Improved diagnosis and treatment of immunologic infertility, as well as identification of proteins for targeted contraception, are dependent on the identification and characterization of relevant sperm antigens. The protein expressed by this gene is recognized by anti-sperm agglutinating antibodies from an infertile woman. Furthermore, immunization of female rats with the recombinant human protein reduced fertility. This protein localizes to the plasma membrane of germ cells in the testis and to the post-acrosomal plasma membrane of mature spermatozoa. Recombinant polypeptide binds GTP and exhibits GTPase activity. Thus, this protein may regulate GTP signal transduction pathways involved in spermatogenesis and fertilization. Two transcript variants of this gene encode the same protein. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-100165907-T-TA is Pathogenic according to our data. Variant chr8-100165907-T-TA is described in ClinVar as [Pathogenic]. Clinvar id is 2102695.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SPAG1	NM_003114.5	c.237dup	p.Pro80ThrfsTer11	frameshift_variant	3/19	ENST00000388798.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SPAG1	ENST00000388798.7	c.237dup	p.Pro80ThrfsTer11	frameshift_variant	3/19	1	NM_003114.5	P1
SPAG1	ENST00000251809.4	c.237dup	p.Pro80ThrfsTer11	frameshift_variant	3/19	5		P1
SPAG1	ENST00000520508.5	c.237dup	p.Pro80ThrfsTer11	frameshift_variant	3/10	5
SPAG1	ENST00000520643.5	c.237dup	p.Pro80ThrfsTer11	frameshift_variant	3/10	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251448 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135904

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461864 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 727234

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: 0.00000719

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia 28 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Oct 28, 2022

For these reasons, this variant has been classified as Pathogenic. This variant has not been reported in the literature in individuals affected with SPAG1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change creates a premature translational stop signal (p.Pro80Thrfs*11) in the SPAG1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SPAG1 are known to be pathogenic (PMID: 24055112). -

Computational scores

Source: dbNSFP v4.3

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: rs886754008; hg19: chr8-101178135;