rs755104973

Positions:

• chr1-25553921-G-C

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PM2 PP3_Strong PP5_Very_Strong

The NM_015627.3(LDLRAP1):​c.89-1G>C variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,296 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 Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LDLRAP1 NM_015627.3 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 9.97

Genes affected

LDLRAP1 (HGNC:18640): (low density lipoprotein receptor adaptor protein 1) The protein encoded by this gene is a cytosolic protein which contains a phosphotyrosine binding (PTD) domain. The PTD domain has been found to interact with the cytoplasmic tail of the LDL receptor. Mutations in this gene lead to LDL receptor malfunction and cause the disorder autosomal recessive hypercholesterolaemia. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 8.5, offset of 2, new splice context is: taccctgtgctaccccacAGctg. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 1-25553921-G-C is Pathogenic according to our data. Variant chr1-25553921-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 4779.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LDLRAP1	NM_015627.3	c.89-1G>C		splice_acceptor_variant		ENST00000374338.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LDLRAP1	ENST00000374338.5	c.89-1G>C		splice_acceptor_variant		1	NM_015627.3	P1
LDLRAP1	ENST00000488127.1	n.558G>C		non_coding_transcript_exon_variant	1/7	2
LDLRAP1	ENST00000485476.2	n.76-1G>C		splice_acceptor_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250356 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135478

Gnomad AFR exome AF: 0.00

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: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461296 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726946

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 4 Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Sep 23, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Oct 19, 2022	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Sep 05, 2003	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Aug 16, 2023	For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 4779). Disruption of this splice site has been observed in individual(s) with autosomal recessive hypercholesterolemia (PMID: 12016260, 15485476, 28965616). It has also been observed to segregate with disease in related individuals. This variant is present in population databases (rs755104973, gnomAD 0.0009%). This sequence change affects an acceptor splice site in intron 1 of the LDLRAP1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in LDLRAP1 are known to be pathogenic (PMID: 11326085, 12464675). -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Jun 23, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D
GERP RS		5.3
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	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.97		Position offset: 3
DS_AL_spliceai		0.99		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs755104973; hg19: chr1-25880412;