rs565513365

Positions:

• chr1-11966985-A-C
• chr1-11966985-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PVS1_Moderate PM2 PP5

The NM_000302.4(PLOD1):​c.1651-2A>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,451,150 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 predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: PLOD1 NM_000302.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 9.26

Genes affected

PLOD1 (HGNC:9081): (procollagen-lysine,2-oxoglutarate 5-dioxygenase 1) Lysyl hydroxylase is a membrane-bound homodimeric protein localized to the cisternae of the endoplasmic reticulum. The enzyme (cofactors iron and ascorbate) catalyzes the hydroxylation of lysyl residues in collagen-like peptides. The resultant hydroxylysyl groups are attachment sites for carbohydrates in collagen and thus are critical for the stability of intermolecular crosslinks. Some patients with Ehlers-Danlos syndrome type VI have deficiencies in lysyl hydroxylase activity. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2015]

PLOD1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.04761905 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-11966985-A-C is Pathogenic according to our data. Variant chr1-11966985-A-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 548602.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PLOD1	NM_000302.4	c.1651-2A>C		splice_acceptor_variant, intron_variant		ENST00000196061.5	NP_000293.2
PLOD1	NM_001316320.2	c.1792-2A>C		splice_acceptor_variant, intron_variant			NP_001303249.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PLOD1	ENST00000196061.5	c.1651-2A>C		splice_acceptor_variant, intron_variant		1	NM_000302.4	ENSP00000196061.4
PLOD1	ENST00000491536.5	n.279-2A>C		splice_acceptor_variant, intron_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1451150 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 722712

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: 9.07e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Ehlers-Danlos syndrome, kyphoscoliotic type 1 Pathogenic:1 Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Genomic Research Center, Shahid Beheshti University of Medical Sciences	Mar 05, 2018	- -
Uncertain significance, criteria provided, single submitter	curation	Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard	May 02, 2023	The homozygous c.1651-2A>C variant in PLOD1 was identified by our study in one individual with Ehlers-Danlos syndrome kyphoscoliotic type 1. The c.1651-2A>C variant in PLOD1 has not been previously reported in individuals with Ehlers-Danlos syndrome kyphoscoliotic type 1. This variant is absent in population databases. This variant has also been reported in ClinVar (Variation ID: 548602) and has been interpreted as pathogenic by the Genomic Research Center, Shahid Beheshti University of Medical Sciences. A different nucleotide change that also results in a splice acceptor variant at the same site, c.1651-2A>G (ClinVar Variation ID: 265507), has been previously reported pathogenic, and the variant being assessed here, c.1651-2A>C, is predicted by SpliceAI to have a similar effect on splicing. This variant is located in the 3' splice region. Computational tools predict a splicing impact, though this information is not predictive enough to determine pathogenicity. There is an in-frame cryptic splice site 39 bases from the intron-exon boundary, providing evidence that this variant may add 13 amino acids instead of causing loss of function. However, this information is not predictive enough to determine pathogenicity. Loss of function of the PLOD1 gene is an established disease mechanism in autosomal recessive Ehlers-Danlos syndrome kyphoscoliotic type 1. In summary, while there is some suspicion for a pathogenic role, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PVS1_Moderate, PS1_Supporting, PM2_Supporting, PM3_Supporting (Richards 2015). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.26
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.97	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.91
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.39		Position offset: 41
DS_AL_spliceai		0.98		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs565513365; hg19: chr1-12027042;