8-96273296-C-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_014754.3(PTDSS1):c.180-3C>T variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000504 in 1,586,900 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000049 (0 hom.)
• Consequence: PTDSS1 NM_014754.3 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.2896
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.76

Genes affected

PTDSS1 (HGNC:9587): (phosphatidylserine synthase 1) The protein encoded by this gene catalyzes the formation of phosphatidylserine from either phosphatidylcholine or phosphatidylethanolamine. Phosphatidylserine localizes to the mitochondria-associated membrane of the endoplasmic reticulum, where it serves a structural role as well as a signaling role. Defects in this gene are a cause of Lenz-Majewski hyperostotic dwarfism. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Mar 2014]

LOC105375652 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.27).
• BS2: High AC in GnomAdExome at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PTDSS1	NM_014754.3	c.180-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000517309.6
LOC105375652	XR_928431.3	n.91-6959G>A		intron_variant, non_coding_transcript_variant
PTDSS1	NM_001290225.2	c.-89-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PTDSS1	ENST00000517309.6	c.180-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_014754.3	P1
PTDSS1	ENST00000337004.8	c.180-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant, NMD_transcript_variant		1
PTDSS1	ENST00000517557.5	n.254-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152200 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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000220 AC: 5 AN: 227362 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 122916

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000175

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: 0.00000488 AC: 7 AN: 1434700 Hom.: 0 Cov.: 28 AF XY: 0.00000280 AC XY: 2 AN XY: 713488

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000156

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000123

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152200 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74356

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: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000189

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 25, 2023

This variant is present in population databases (rs761332437, gnomAD 0.02%). This sequence change falls in intron 1 of the PTDSS1 gene. It does not directly change the encoded amino acid sequence of the PTDSS1 protein. It affects a nucleotide within the consensus splice site. This variant has not been reported in the literature in individuals affected with PTDSS1-related conditions. 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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. ClinVar contains an entry for this variant (Variation ID: 1441319). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.27
Cadd	Benign	16
Dann	Benign	0.90

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.29
dbscSNV1_RF	Benign	0.13
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: rs761332437; hg19: chr8-97285524;