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
Any Coats plus syndrome in which the cause of the disease is a mutation in the CTC1 gene.
Features include always present findings: Cerebral calcification and Leukoencephalopathy; and very common findings: Intrauterine growth retardation. 44 total HPO annotations.
Organ System | Phenotype Count | Example Features |
|---|---|---|
Brain and nerves | 11 | Hemiplegia, Dystonia, Seizure |
Bones and joints | 8 | Short femoral neck, Weak and brittle bones (osteoporosis), Mild bone density loss (osteopenia) |
Skin | 5 | Nail dysplasia, Retinal telangiectasia, Gastrointestinal telangiectasia |
Blood and immune system | 4 | Intestinal bleeding, Low red blood cell count (anemia), Oral leukoplakia |
Eyes | 4 | Blindness, Retinal telangiectasia, Damage to the optic nerve (optic atrophy) |
Growth and development | 3 | Short stature, Postnatal growth retardation, Intrauterine growth retardation |
Digestive system | 2 | Intestinal bleeding, Gastrointestinal telangiectasia |
Muscles | 1 | Damage to the optic nerve (optic atrophy) |
Lungs and breathing | 1 | Lung scarring (pulmonary fibrosis) |
The classic dyskeratosis congenita (DC) triad of abnormal fingernails and toenails, lacy, reticular pigmentation of the neck and upper chest, and oral leukoplakia is diagnostic; however, these features are not present in all individuals with DC and related telomere biology disorders (DC/TBD) and may or may not develop over time after the appearance of other complications listed here [, , , ]. The time of onset for these medical complications varies considerably among individuals even within the same family and thus the manifestations of DC/TBD do not progress in a predictable pattern.
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
CTC1 encodes CST telomere replication complex component 1 (1,217 aa). Component of the CST complex proposed to act as a specialized replication factor promoting DNA replication under conditions of replication stress or natural replication barriers such as the telomere duplex. Highest expression in Brain Cerebellum (50.0 TPM) and Brain Cerebellar Hemisphere (43.2 TPM).
Cerebroretinal microangiopathy with calcifications and cysts 1 is caused by mutations in the CTC1 gene on chromosome 17.
The CTC1 protein participates in The polymerase component of DNA polymerase alpha:primase synthesizes a 20-nucleotide primer on the G strand of the telomere and The primase component of DNA polymerase:primase synthesizes a 6-10 nucleotide RNA primer on the G strand of the telomere pathways.
CTC1 is classified as a druggable target (Clinically Actionable and Enzyme categories) with score 0.0.
Due to the rarity of DC/TBD, no specific genotype-phenotype correlations have been identified.
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
The penetrance of DC/TBD and DC/TBD-associated medical complications is not well understood. Due to the variability between individuals (even within the same family) and the observation that medical complications may increase with age, penetrance may appear reduced. Recent studies report somatic TERT promotor variants as possible modifiers to germline pathogenic variants . However, additional studies are needed to further understand the components leading to variable penetrance of DC/TBD-causing variants.
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
Dyskeratosis congenita and related telomere biology disorders (DC/TBD) are caused by impaired telomere maintenance resulting in short or very short telomeres. The phenotypic spectrum of telomere biology disorders is broad and includes individuals with classic dyskeratosis congenita (DC) as well as those with very short telomeres and an isolated physical finding [, , , , , ]. The criteria for classic DC were described by ; see . Note, however, that individuals may develop features of a DC/TBD at variable rates and ages, which can make proper diagnosis challenging.
A telomere biology disorder (TBD), including dyskeratosis congenita (DC), should be suspected in individuals with the following clinical findings. Physical characteristics. One of the following:
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
Disorders with clinical features that overlap those of dyskeratosis congenita and related telomere biology disorders (DC/TBD) are described below. Disorders with Nail Dysplasia Table 3. Disorders with Nail Dysplasia in the Differential Diagnosis of Dyskeratosis Congenita and Related Telomere Biology Disorders (DC/TBD)
Gene | Disorder | MOI | Clinical Characteristics | Comment |
|---|---|---|---|---|
FZD6 | Twenty-nail dystrophy (OMIM 161050) | AR | Onychauxis, hyponychia, onycholysis |
Genetic testing for CTC1 is available. Testing is considered confirmatory for diagnosis.
No approved treatments are currently available for cerebroretinal microangiopathy with calcifications and cysts 1. The disease remains an area of unmet medical need.
Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with dyskeratosis congenita (DC) or a related telomere biology disorder (TBD), it is important to note that the clinical spectrum of DC/TCB is broad and signs and symptoms develop at various ages and rates. The evaluations summarized (if not performed as part of the evaluation that led to the diagnosis) are recommended. Table 5. Recommended Evaluations Following Initial Diagnosis in Individuals with Dyskeratosis Congenita and Related Telomere Biology Disorders (DC/TBD)
System/Concern | Evaluation | Comment |
|---|---|---|
Dermatologic | Thorough skin nail exam | — |
Dental | Baseline eval for oral hygiene, leukoplakia, oral squamous cell cancer | — |
Otolaryngologic | Baseline eval for leukoplakia squamous cell head/neck cancer | Growth |
development | Clinical assessment | — |
Ophthalmic | Thorough exam for complications related to lacrimal duct stenosis, abnormal eyelash growth, retinal disorders incl exudative retinopathy | Gastrointestinal |
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
Blood transfusions
Transfusions of red cells or platelets should be avoided or minimized for those who are candidates for hematopoietic cell transplantation (HCT).
To minimize the chances of sensitization, family members must not act as blood donors if HCT is being considered.
All blood products should be leukodepleted and irradiated.
Radiation. It is prudent to minimize exposure to therapeutic radiation as data on radiation side effects are limited. Androgens and growth factors. The combination of androgens and granulocyte colony-stimulating factor was associated with splenic peliosis ("blood lakes") and rupture in two individuals; thus, the combination should be avoided . Cancer prevention. Given the increased susceptibility of individuals with DC/TBD to developing leukemias and other malignancies, individuals with DC/TBD are advised to avoid toxic agents that have been implicated in tumorigenesis (including smoking cigarettes or drinking alcohol), to use sunscreen regularly, and to avoid excessive sun exposure.
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
Search ClinicalTrials.gov in the US and EU Clinical Trials Register in Europe for information on clinical studies for a wide range of diseases and conditions. Note: There may not be clinical trials for this disorder.
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
View trials for cerebroretinal microangiopathy with calcifications and cysts 1
The recommendations in this section were discussed at the first DC clinical research workshop in 2008 and updated in 2014 at a consensus conference that led to publication of the first edition of the Dyskeratosis Congenita and Telomere Biology Disorders: Diagnosis and Management Guidelines . Because of the rarity of DC/TBD, the recommendations are not based on large-scale clinical trials. Table 7. Recommended Surveillance for Individuals with Dyskeratosis Congenita and Related Telomere Biology Disorders (DC/TBD)
System/Concern | Evaluation | Frequency |
|---|---|---|
for BMF | CBC | Prior to start; Rpt every 4-6 wks; When counts are stable, rpt every 2-3 mos Liver function tests |
Cancer | Self-exam for oral, head, neck cancers | Monthly; Cancer screening by otolaryngologist; Gynecologic exam; Skin cancer screening by dermatologist |
Pulmonary fibrosis | PFTs | Annually starting at age 8 yrs (or at diagnosis) Pulmonary arteriovenous |
malformations | Bubble echocardiogram | In case of pulmonary symptoms in absence of pulmonary fibrosis Oral dental issues |
Immunologic issues | Follow up based on findings at initial eval | At immunologist's discretion Cutaneous |
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
Phenotype severity distribution: 2 always present features, 1 very common feature, 4 common features.
No clinical trials have been registered for cerebroretinal microangiopathy with calcifications and cysts 1.
11 publications have been identified in PubMed for cerebroretinal microangiopathy with calcifications and cysts 1. Research spans Case Report / Case Series (64%), Review / Meta-Analysis (18%), and Basic Science / Preclinical (9%).
Research Type | Count | % of Total |
|---|---|---|
Patient case studies | 7 | 64% |
Research summaries | 2 | 18% |
Laboratory research | 1 | 9% |
New treatment approaches | 1 | 9% |
Foley MJ (2026). [PMID: 42196799](https://pubmed.ncbi.nlm.nih.gov/42196799/). *Diagnostics (Basel)*. [Case Report / Case Series]
Gowda VK (2026). [PMID: 41554616](https://pubmed.ncbi.nlm.nih.gov/41554616/). *BMJ case reports*. [Case Report / Case Series]
Zhou H (2026). [PMID: 41575730](https://pubmed.ncbi.nlm.nih.gov/41575730/). *Journal of assisted reproduction and genetics*. [Gene Therapy / Novel Therapeutics]
Ozen F (2026). [PMID: 41387117](https://pubmed.ncbi.nlm.nih.gov/41387117/). *Clinical genetics*. [Case Report / Case Series]
Kojima M (2025). [PMID: 40973993](https://pubmed.ncbi.nlm.nih.gov/40973993/). *Pediatric transplantation*. [Review / Meta-Analysis]
Jiang T (2025). [PMID: 40555664](https://pubmed.ncbi.nlm.nih.gov/40555664/). *Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics*. [Review / Meta-Analysis]
Serrão C (2025). [PMID: 40953348](https://pubmed.ncbi.nlm.nih.gov/40953348/). *Neurology*. [Case Report / Case Series]
Kvarnung M (2025). [PMID: 39616267](https://pubmed.ncbi.nlm.nih.gov/39616267/). *European journal of human genetics : EJHG*. [Case Report / Case Series]
Srour L (2025). [PMID: 40440483](https://pubmed.ncbi.nlm.nih.gov/40440483/). *Aging*. [Basic Science / Preclinical]
Chaaya C (2025). [PMID: 40359402](https://pubmed.ncbi.nlm.nih.gov/40359402/). *Ophthalmic surgery, lasers & imaging retina*. [Case Report / Case Series]
Data assembled from 7 of 12 sources · Last updated Sep 20, 2026, 8:44 AM UTC
Online Mendelian Inheritance in Man
Genetic and Rare Diseases Info Center
Nail-patella syndrome | AD | Classic clinical tetrad of changes in nails, knees, elbows, presence of iliac horns | Nails may be absent, hypoplastic, or dystrophic; ridged longitudinally or horizontally; pitted; discolored; separated into 2 halves by longitudinal cleft or ridge of skin; thin or (less often) thickened. USB1 | — |
Poikiloderma with neutropenia | AR | Post-inflammatory poikiloderma chronic noncyclic neutropenia typically assoc w/recurrent sinopulmonary infections (often) bronchiectasis. risk for myelodysplastic syndrome. Other findings incl nail dystrophy palmar/plantar hyperkeratosis. | Thickened, hyperkeratotic toenails are common; dystrophic nails that can slough may also be seen. | — |
Gene | Disorder | MOI | Clinical Characteristics | Comment BRCA1 BRCA2 BRIP1 ERCC4 FAAP100 FANCA FANCB FANCC FANCD2 FANCE FANCF FANCG FANCI FANCL FANCM PALB2 RAD51 RAD51C REV7 RFWD3 SLX4 UBE2T |
XRCC2 | Fanconi anemia (FA) | ARXLAD1 | The primary clinical features of FA are physical abnormalities, progressive BMF manifesting as pancytopenia, cancer susceptibility; however, some persons w/FA have neither physical abnormalities nor BMF. | The 1st clinical manifestation of both FA DC/TBD may be BMF. DNAJC21 EFL1 SBDS |
SRP54 | Shwachman-Diamond syndrome (SDS) | ARAD2 | Exocrine pancreatic dysfunction w/malabsorption, malnutrition, growth failure; hematologic abnormalities w/single- or multi-lineage cytopenias susceptibility to MDS AML; bone abnormalities. In almost all affected children, persistent or intermittent neutropenia is a common presenting finding. | — |
Source: GeneReviews — "Dyskeratosis Congenita and Related Telomere Biology Disorders"
History of potential swallowing difficulties /or enteropathy; baseline liver function tests |
— |
Genitourinary | For males, assessment for urethral stenosis | — |
Musculoskeletal | Consideration of baseline bone mineral density scan at age 14 yrs or at diagnosis; history of any joint problems | — |
Neurologic | If early-onset neurologic findings (e.g., ataxia) or many complications are found in other initial evals, consider brain MRI to evaluate for cerebellar hypoplasia or intracranial calcifications. | — |
Hematologic | Eval by hematologist incl CBC bone marrow aspiration biopsy to determine if signs of BMF are present | Consideration of HLA typing of affected person, unaffected sibs, parents in anticipation of possible need for HCT Pulmonary |
Cardiologic | Baseline eval for cardiac malformations | Genetic |
counseling | By genetics professionals1 | To obtain a pedigree inform affected persons their families re nature, MOI, implications of DC/TBD to facilitate medical personal decision making Family support resources |
manifestations |
Full-body skin exam by dermatologist |
Annually |
Developmental delay | Clinical eval referral to specialist if needed | At each visit in childhood Opht... |