Kisho is an information platform, not a medical provider. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. All content is aggregated from publicly available sources (including ClinicalTrials.gov, PubMed, FDA.gov, and Orphanet) and is provided for informational purposes only. Clinical trial eligibility, treatment decisions, and any health-related actions should always be discussed with a qualified healthcare professional. Kisho does not endorse any specific therapy, organization, or clinical trial. Terms of use · Privacy policy
Features include always present findings: Stomatocytosis, Carotid artery stenosis, Low red blood cell count (anemia), and Giant platelets and others. 23 total HPO annotations.
Organ System | Phenotype Count | Example Features |
|---|---|---|
Blood and immune system | 9 | Abnormal bleeding tendency (abnormal bleeding), Low red blood cell count (anemia), Giant platelets |
ABCG8 encodes ATP binding cassette subfamily G member 8 (673 aa). ABCG5 and ABCG8 form an obligate heterodimer that mediates Mg(2+)- and ATP-dependent sterol transport across the cell membrane. Highest expression in Liver (48.1 TPM) and Small Intestine Terminal Ileum (4.0 TPM).
Sitosterolemia 1 is associated with mutations in the ABCG8 gene on chromosome 2.
The ABCG8 protein participates in Expression of ABCG8 regulated by NR1H2 or NR1H3 and Defective ABCG8 (in ABCG5:ABCG8) does not transport sterols from cytosol to extracellular region pathways.
ABCG8 is classified as a druggable target (Abc Transporter, Druggable Genome, and Transporter categories) with score 2.1.
41 pathogenic variants reported in ABCG8 in ClinVar, including hotspot variants 872257 and 713037.
Formal diagnostic criteria for sitosterolemia have not been established.
Sitosterolemia should be suspected in individuals with the following:
Source: GeneReviews — "Sitosterolemia"
No approved treatments are currently available for sitosterolemia 1. The disease remains an area of unmet medical need.
Evaluations Following Initial Diagnosis Table 3. Recommended Evaluations Following Initial Diagnosis in Individuals with Sitosterolemia
Table 5.
Recommended Annual Surveillance for Individuals with Sitosterolemia
System/Concern | Evaluation
| • Plasma concentrations of plant sterols (primarily beta-sitosterol campesterol) cholesterol
No clinical trials have been registered for sitosterolemia 1.
6 publications have been identified in PubMed for sitosterolemia 1. Research spans Case Report / Case Series (67%), Review / Meta-Analysis (17%), and Epidemiology / Natural History (17%).
Okada T (2026). [PMID: 41672494](https://pubmed.ncbi.nlm.nih.gov/41672494/). *Journal of atherosclerosis and thrombosis*. [Review / Meta-Analysis]
Alves AC (2025). [PMID: 41130816](https://pubmed.ncbi.nlm.nih.gov/41130816/). *Journal of clinical lipidology*. [Case Report / Case Series]
Do TTM (2025). [PMID: 39860331](https://pubmed.ncbi.nlm.nih.gov/39860331/). *Journal of clinical medicine*. [Case Report / Case Series]
Huang S (2025). [PMID: 40115465](https://pubmed.ncbi.nlm.nih.gov/40115465/). *Translational pediatrics*. [Epidemiology / Natural History]
Marrero-Cepeda C (2025). [PMID: 41023734](https://pubmed.ncbi.nlm.nih.gov/41023734/). *Thrombosis journal*. [Case Report / Case Series]
Data assembled from 7 of 12 sources · Last updated Sep 19, 2026, 1:58 AM UTC
Online Mendelian Inheritance in Man
Lab test results |
2 |
Elevated LDH (tissue damage marker) (increased circulating lactate dehydrogenase concentration), Elevated circulating sitosterol concentration |
Digestive system | 2 | Enlarged spleen (splenomegaly), Abdominal pain |
Bones and joints | 2 | Joint inflammation (arthritis), Arthralgia |
Eyes | 1 | Corneal arcus |
Heart and blood vessels | 1 | Coronary artery atherosclerosis |
To date, approximately 110 individuals with biallelic pathogenic variants in ABCG5 and/or ABCG8 have been reported [, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ]. The following description of the phenotypic features associated with this condition is based on these reports. Presentation. The clinical presentation of sitosterolemia varies from xanthomas and atherosclerosis and its complications to a milder phenotype with few to no specific symptoms and signs . Hypercholesterolemia. Individuals with sitosterolemia show an unexpected significant lowering of plasma cholesterol level in response to low-fat or low plant-derived food diet modification or to bile acid sequestrant therapy, and do not respond to statin therapy.
Source: GeneReviews — "Sitosterolemia"
Variant
Significance |
|---|
Review Stars |
|---|
Hotspot |
|---|
872257 | Conflicting classifications of pathogenicity | — | Yes |
713037 | Conflicting classifications of pathogenicity | — | Yes |
596946 | Conflicting classifications of pathogenicity | — | Yes |
596119 | Conflicting classifications of pathogenicity | — | Yes |
546173 | Pathogenic | 2 stars | Yes |
No genotype-phenotype correlations for ABCG5 and ABCG8 have been identified.
Source: GeneReviews — "Sitosterolemia"
Hereditary Disorders in the Differential Diagnosis of Sitosterolemia Table 2. Genes of Interest in the Differential Diagnosis of Sitosterolemia
Gene(s) | DiffDx Disorder | MOI | Features of DiffDx Disorder |
|---|---|---|---|
ABCA1 | Tangier disease (analphalipoproteinemia) | AR | Stomatocytosis |
PCSK9 | Familial hypercholesterolemia1 (also called heterozygous FH) | AD | Xanthomas in children |
Not assoc w/macro-thrombocytopenia Homozygous FH2 | AD | Xanthomas in children | Both parents of affected child have hypercholesterolemia.; LDL-C levels are generally 500 mg/dL in untreated adults (levels can be lower in children).; Not assoc w/macro-thrombocytopenia CYP27A1 |
Cerebrotendinous xanthomatosis | AR | Xanthomas in children | concentrations of plasma cholestanol, childhood-onset protracted diarrhea, cataracts; Typically, neurologic involvment in affected adults |
LCAT | Lecithin-cholesterol aceyl transferase (LCAT) deficiency (OMIM 245900) | AR | Stomatocytosis |
Source: GeneReviews — "Sitosterolemia"
Genetic testing for ABCG8 is available. Testing is considered confirmatory for diagnosis.
Evaluation |
|---|
Comment |
|---|
levels | Measure plasma concentrations of plant sterols (primarily beta-sitosterol campesterol) cholesterol. | — |
Xanthomas | Determine size, number, distribution of xanthomas (tendon tuberous). | — |
Heart | Cardiology consultation to evaluate for atherosclerosis cardiac valve abnormalities | Consider use of coronary artery calcium score (from cardiac CT) or coronary arteriography as needed. Hematologic abnormalities |
Liver | Baseline liver function (albumin, ALT, AST, ALP, bilirubin) | — |
Spleen | Evaluate for splenomegaly. | If present, consultation w/hematologist gastroenterologist |
Joints | Evaluate for arthralgias /or arthritis. | Genetic |
counseling | By genetics professionals1 | To inform individuals families re nature, MOI, implications of sitosterolemia in order to facilitate medical personal decision making CBC = complete blood count; MOI = mode of inheritance 1. |
Treatment of Manifestations in Individuals with Sitosterolemia Manifestation | Treatment | Considerations/Other Elevated plant |
Source: GeneReviews — "Sitosterolemia"
Margarines and other products containing stanols (e.g., campestanol and sitostanol), which are recommended for use by persons with hypercholesterolemia, are contraindicated in those with sitosterolemia as they can exacerbate plant stanol accumulation . Note: Foods with high plant sterol content including shellfish, vegetable oils, margarine, nuts, avocados, and chocolate should be taken in moderation due to increased intestinal absorption of plant sterols in those with sitosterolemia .
Source: GeneReviews — "Sitosterolemia"
Search ClinicalTrials.gov in the US and EU Clinical Trials Register in Europe for access to information on clinical studies for a wide range of diseases and conditions.
Source: GeneReviews — "Sitosterolemia"
View trials for sitosterolemia 1
| CBC platelet count
| Liver transaminases
Atherosclerosis coronary artery disease (esp in those w/longstanding untreated sitosterolemia) | Noninvasive imaging to exclude coronary carotid plaque as well as valvular atherosclerotic manifestations
CBC = complete blood count
Source: GeneReviews — "Sitosterolemia"
Phenotype severity distribution: 13 always present features.
AI-curated news mentioning sitosterolemia 1
Updated Aug 19, 2026
Recent research highlights evolving strategies for the earlier diagnosis of sitosterolemia, a rare lipid metabolism disorder. Improved diagnostic approaches could enhance patient outcomes by facilitating timely interventions.
A new catalog details pathogenic variants in the ABCG5 and ABCG8 genes associated with sitosterolemia, providing insights into the clinical features of this rare condition. This research enhances understanding of genetic factors influencing sitosterolemia.
A study identifies a novel compound heterozygous mutation in the ABCG5 gene linked to early-onset sitosterolemia. This research enhances understanding of the genetic basis of the disease and may inform future therapeutic strategies.