# NM_000527.5(LDLR):c.1942T>C (p.Ser648Pro)

https://sugi.bio/variant/ldlr-p-ser648pro

## Summary

**LDLR p.Ser648Pro (c.1942T>C)** is classified **Likely pathogenic** in LDLR (ClinVar, Expert panel, 5 submitters; last evaluated 2023-04-28). AlphaMissense: likely pathogenic (0.6599); Absent from gnomAD v4.1; Associated with hypercholesterolemia, familial, 1.

**At a glance:** Likely pathogenic · review: Expert panel · rsID rs879255079 · 5 submitters · 2 linked conditions · AlphaMissense likely pathogenic · absent from gnomAD v4.1

## For patients & families {#patients}

This is a change in the LDLR gene that is considered likely disease-causing, submitted by 5 submitters, and is linked to hypercholesterolemia, familial, 1.

*Reference information, not medical advice, and not a prediction for any individual. A genetic counselor or clinician can interpret what it means for you and your family.*

|  |  |
| --- | --- |
| Clinical trials | 28 registered for this condition — see ClinicalTrials.gov |

**Support & next steps:** [Condition overview & support (NIH GARD)](https://rarediseases.info.nih.gov/diseases/0024574/index) · [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [LDLR](https://sugi.bio/atlas/gene/LDLR/) |
| Protein change (HGVS p.) | p.Ser648Pro |
| Coding change (HGVS c.) | c.1942T>C |
| MANE Select transcript | [NM_000527](https://www.ncbi.nlm.nih.gov/nuccore/NM_000527) |
| dbSNP | [rs879255079](https://www.ncbi.nlm.nih.gov/snp/rs879255079/) |
| Variant type | single nucleotide variant |
| Location | chr19:11120188-11120188 (GRCh38) |
| ClinVar | [VCV252120](https://www.ncbi.nlm.nih.gov/clinvar/variation/252120/) |

**All HGVS expressions:** `LRG_274:g.35808T>C`, `LRG_274t1:c.1942T>C`, `NC_000019.10:g.11120188T>C`, `NC_000019.9:g.11230864T>C`, `NG_009060.1:g.35808T>C`, `NM_000527.5:c.1942T>C`, `NM_001195798.2:c.1942T>C`, `NM_001195799.2:c.1819T>C`, `NM_001195800.2:c.1438T>C`, `NM_001195803.2:c.1561T>C`

## Computational & population evidence {#evidence}

**Concordance:** 1 independent predictor **concordant** with the ClinVar classification.

- AlphaMissense **likely pathogenic** (0.6599) — concordant with the pathogenic call
- REVEL 0.604 (indeterminate)
- SaProt LLR -9.099 (tolerated) — differs from AlphaMissense
- → **In-silico consensus:** AlphaMissense calls this damaging; SaProt does not; REVEL is indeterminate
- Conservation: phyloP 5.932, GERP 2.22, phastCons 1 — highly conserved (agrees)
- CADD: **PHRED 22.5**. No single ClinGen-calibrated threshold exists and the expert panels that use CADD disagree — GUCY2D/AIPL1 require ≥ 20.0 for an untranslated-region variant, ABCA4 ≥ 28.1 for a synonymous or indel variant, the Pulmonary Hypertension panel imports Pejaver 2022's missense-calibrated numbers, and the Antibody Deficiencies panel declines CADD entirely for PIK3CD. CADD v1.7 also incorporates Zoonomia phyloP, so it partly re-expresses the conservation above. *Descriptive; no threshold applied.*
- Regional missense constraint: **o/e 1.00** across the covering region of the MANE Select transcript (11,089,549–11,131,313), spanning 41,764 bp. Chi-square p 0.91. Describes the region, not this allele; gnomAD v4.1.1's own constrained determination. *Descriptive; no ACMG code applied.*
- SpliceAI: **no splice effect predicted**. SpliceAI outputs four numbers per variant, not one: acceptor loss, donor loss, acceptor gain, donor gain (DS_AL / DS_DL / DS_AG / DS_DG). A loss score is an existing splice site weakened or destroyed; a gain score is a new site created or an existing one strengthened. The release publishes its own filter rule, which we read from the dataset rather than assume: an allele is reported only if the largest of its four deltas reaches 0.2. No allele at this position is in the release, so all four are under 0.2 for every alternate allele here. No figure is shown because none was read: the bound is deduced from that absence. It is a result, not a gap in our data, because the release scores every possible substitution across the transcripts it covers (Ensembl MANE v1.4) before it filters, so what survives for a gene is one continuous stretch. What is measured is that this position sits inside the stretch covered for LDLR (717 scored positions, the nearest 10 bases away); what is taken from the release's own description, rather than measured, is that coverage inside that stretch is continuous. On that, SpliceAI did score it. *ClinGen's SVI treats the largest of the four as evidence against a splicing effect at or below 0.1, where it may support BP4, and as uninformative between 0.1 and 0.2. We cannot tell which applies here, so these SpliceAI data support neither BP4 nor PP3; that is a statement about this evidence alone, not about the variant's other evidence.*
- Population frequency: **absent from gnomAD v4.1** — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

*Computational predictors are not independent (ClinGen Variant Classification guidance): AlphaMissense (Cheng et al. 2023) carries the ACMG weight for missense and conservation (phyloP/GERP/phastCons) for non-missense; REVEL (Pejaver-2022 calibrated strength bands) and SaProt (Su et al. 2023, structure-aware, ClinVar-independent protein language model, raw LLR) are shown as orthogonal agreement signals, not additive. For frequency, the gnomAD v4.1 grpmax filtering allele frequency (FAF95) is ClinGen's designated BA1/BS1 input (gnomAD v4 guidance v3.0, June 2025); BA1/BS1 thresholds are disease-specific, not a blanket 5%. Predictions, not a clinical determination.*

## Gene constraint & dosage {#gene-context}

**LDLR** population constraint: LOEUF 1.091, pLI 1.2477e-30, missense-Z 0.60522; ClinGen dosage — haploinsufficiency 3/3, triplosensitivity 0/3. *Lower LOEUF and higher pLI indicate a gene that tolerates loss-of-function poorly; ClinGen dosage is the curated haploinsufficiency call.*

Curated gene–disease validity (ClinGen):

- **hypercholesterolemia, familial, 1** — Definitive (SD)

## Protein context {#protein}


AlphaFold model confidence (whole protein): pLDDT 75.81, 29% of residues very-high.

**36 experimental structure(s)** (PDB): [1AJJ](https://www.rcsb.org/structure/1AJJ), [1D2J](https://www.rcsb.org/structure/1D2J), [1F5Y](https://www.rcsb.org/structure/1F5Y), [1F8Z](https://www.rcsb.org/structure/1F8Z), [1HJ7](https://www.rcsb.org/structure/1HJ7), [1HZ8](https://www.rcsb.org/structure/1HZ8) — incl. mutant structure 2W2N.

## What this gene does {#gene-function}

*Describes the biological roles of LDLR (the gene this variant disrupts) — not effects measured for this specific variant. A damaging variant is expected to affect these functions and pathways; the degree depends on the variant.*

**How this variant is thought to act:** LDLR's established molecular role includes protease binding.


### Pathways affected {#pathways}

LDLR participates in **5 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [Cargo recognition for clathrin-mediated endocytosis](https://reactome.org/content/detail/R-HSA-8856825) | curated |
| [Clathrin-mediated endocytosis](https://reactome.org/content/detail/R-HSA-8856828) | curated |
| [LDL clearance](https://reactome.org/content/detail/R-HSA-8964038) | curated |
| [Chylomicron clearance](https://reactome.org/content/detail/R-HSA-8964026) | electronic |
| [Retinoid metabolism and transport](https://reactome.org/content/detail/R-HSA-975634) | electronic |

### Molecular function & processes (GO — experimentally supported) {#go}

**Molecular function:** protease binding, low-density lipoprotein particle receptor activity, low-density lipoprotein particle binding, very-low-density lipoprotein particle receptor activity, identical protein binding, molecular adaptor activity.

**Biological process:** negative regulation of receptor recycling, long-term memory, negative regulation of low-density lipoprotein particle clearance, intestinal cholesterol absorption, cholesterol transport, low-density lipoprotein particle clearance.

## Clinical significance {#significance}

**Likely pathogenic** — review status Expert panel *(reviewed by expert panel)*, last evaluated 2023-04-28.

**Submitter consensus:** unanimous (5/5 Likely pathogenic).

**Submission history:** 5 submissions (2016–2023); classifications have been stable.

**ClinGen expert panel:** Likely Pathogenic — Familial Hypercholesterolemia VCEP (hypercholesterolemia, familial). *Expert-panel curated (ACMG); the highest ClinVar review tier.*
**Applied ACMG criteria (met):** `PM2`, `PS3`, `PP4`.
*Considered but not met:* `PM6`, `PVS1`, `PS1`, `PS2`, `PS4`, `PM1`, `PP1`, `PP3`, `BS2`, `PM3`, `BS1`, `BS4`, `BS3`, `BP7`, `PM5`, `BP4`, `BP2`, `BA1`, `PM4`.
Inheritance: Semidominant inheritance.

> **Curation rationale (ClinGen, verbatim):** The NM_000527.5(LDLR):c.1942T>C (p.Ser648Pro) variant is classified as Likely pathogenic for Familial Hypercholesterolemia by applying evidence codes (PS3, PM2 and PP4) as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (https://doi.org/10.1016/j.gim.2021.09.012).  The supporting evidence is as follows: PS3 -  2 Level 1 assays: PMID  25386756: Heterologous cells (CHO), FACS assays - result - 50% cell surface LDLR and binding and 26% uptake. PMID 23021490: Heterologous cells (CHO), 125I-LDL and WB assays - result - 30-50% LDLR activity; reduced mature protein. ---- activity is below 70% of wild-type, so functional studies are consistent with damaging effect and PS3 is Met. PM2 - This variant is absent from gnomAD (gnomAD v2.1.1), so PM2 is Met. PP4 - Variant meets PM2 and is identified in 1 index cases who fulfills  SB possible criteria for FH from Cardiovascular Research Group, Instituto Nacional de Saude Doutor Ricardo Jorge, so PP4 is met.
*Source: https://cspec.clinicalgenome.org/cspec/ui/svi/affiliation/50004 · approved 2023-04-28 · [ClinGen Evidence Repository](https://erepo.genome.network/evrepo/ui/classification/5486373f-4e03-4ac7-b53e-fce531d34ddf).*
*These are ClinGen's applied codes, reported verbatim — Sugi Variant does not re-tally or combine them into its own classification.*

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| LDLR-LOVD, British Heart Foundation | Likely pathogenic | criteria provided, single submitter | literature only | 2016-03-25 |
| Cardiovascular Research Group, Instituto Nacional de Saude Doutor Ricardo Jorge | Likely pathogenic | criteria provided, single submitter | research | 2016-03-01 |
| GeneDx | Likely pathogenic | criteria provided, single submitter | clinical testing | 2022-05-23 |
| Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Likely pathogenic | criteria provided, single submitter | clinical testing | 2023-05-22 |
| ClinGen Familial Hypercholesterolemia Variant Curation Expert Panel | Likely pathogenic | reviewed by expert panel | curation | 2023-04-28 |

## Associated conditions {#conditions}

[hypercholesterolemia, familial, 1](https://sugi.bio/atlas/disease/hypercholesterolemia-familial-1/), [familial hypercholesterolemia](https://sugi.bio/atlas/disease/familial-hypercholesterolemia/).

**Reported phenotype names (ClinVar):** Hypercholesterolemia, familial, 1, not provided, Familial hypercholesterolemia, Familial hypercholesterolemias, Familial hypercholesterolaemia, LDL RECEPTOR DISORDER, Hyperlipoproteinemia Type IIa, HYPER-LOW-DENSITY-LIPOPROTEINEMIA, HYPERCHOLESTEROLEMIC XANTHOMATOSIS, FAMILIAL, Fredrickson type IIa hyperlipoproteinemia.

## Same-residue context {#hotspot}

Residue **648** carries **1 other pathogenic ClinVar variant** — a recurrently-mutated position: [LDLR p.Ser648fs](/variant/ldlr-p-ser648fs). *Positional co-occurrence of independent ClinVar records, not functional proof.*

## Similar variants {#similar}

Related LDLR variant pages (same residue, condition, or type): [LDLR p.Ser648Ala](/variant/ldlr-p-ser648ala), [LDLR p.Ser648Phe](/variant/ldlr-p-ser648phe), [LDLR p.Ser648=](/variant/ldlr-p-ser648), [LDLR p.Ser648fs](/variant/ldlr-p-ser648fs), [LDLR c.1186+5G>A](/variant/ldlr-c-1186-plus-5g-a), [LDLR c.1359-1G>A](/variant/ldlr-c-1359-minus-1g-a), [LDLR c.1359-5C>G](/variant/ldlr-c-1359-minus-5c-g), [LDLR c.1705+2T>C](/variant/ldlr-c-1705-plus-2t-c).

### Data sources & attribution {#sources}

ClinVar (NCBI — public domain, built 2026-10-14); gnomAD v4.1 (Broad Institute, built 2026-10-15); AlphaMissense (Cheng et al. 2023, © Google DeepMind — CC BY 4.0, built 2026-01-27); REVEL (Ioannidis et al. 2016 — ODbL, built 2026-07-13); SaProt (Su et al. 2023 — MIT, built 2026-10-14); SpliceAI (Illumina — free for non-commercial use, built 2026-10-13); CADD (Rentzsch et al. 2019, University of Washington — free for non-commercial use, built 2026-10-10); Conservation (phyloP/phastCons/GERP) (UCSC hg38 470-way mammal (Hiller Lab) + Ensembl Compara, built 2026-07-12); gnomAD Non-coding Constraint (Gnocchi) (Chen et al. 2024, Broad Institute — CC0, built 2026-10-11); gnomAD Regional Missense Constraint (Broad Institute — CC0, built 2026-10-13); Pangolin (Zeng & Li 2022 — CC BY 4.0, built 2026-10-11); Repeat regions (UCSC — RepeatMasker, TRF, segmental duplications, built 2026-10-11); ClinGen (ClinGen, built 2026-09-22); UniProt (CC BY 4.0); Reactome / GO (CC BY 4.0, built 2026-09-23); MaveDB (per-record license, built 2026-10-11); CIViC (CC0, built 2026-09-22); Orphanet (Orphanet, built 2026-06-12)

*Primary record: NCBI ClinVar (variation 252120). Classifications reflect these databases as of the page's build date and may change. Free reference use — not medical advice; consult the primary submitters and a clinician.*