Characterizing the Genotype and Phenotype in Adults With Bardet-Biedl Syndrome

NCT05400278 | Completed

• 1 other identifier: 166639
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Bardet-Biedl syndrome (BBS; OMIN #209900) is a rare genetic disorder characterized by six core features: rod-cone dystrophy (retinitis pigmentosa), polydactyly, obesity, genital anomalies, renal anomalies, and learning difficulties. This study aims to contribute to genetic and medical knowledge of BBS, and to provide information on quality of life in adults with BBS and their close relatives. Participants will undergo medical assessments (ocular, oral, and physical examinations) and self-reporting of quality of life, diet, cognitive and emotional symptoms. There are some known genotype-phenotype associations in BBS and participants will be offered genetic testing. It is important to map both genotype and associated phenotype in order to provide optimal treatment and follow-up. Individuals with BBS, age 16 years or older, will be invited to participate. The investigators expect to enroll at least 25 male and female adults with BBS and 15 of their parents to participate in qualitative interviews. These interviews will investigate parents' experiences having a child with BBS, satisfaction with health care services, experience with social and family life, and psychological health.

Conditions

Bardet-Biedl Syndrome

Keywords

Retinitis Pigmentosa; Obesity; Polydactyly; Bardet-Biedl Syndrome; Cognitive deficits

Outcome Measures

Primary Outcomes (3)

• The Medical Outcome Study 36-item Short Form Health Survey (SF-36)

  Health related quality of life (HRQOL) including measures of Physical and mental HRQOL. The SF-36 is a generic quality of life scale which has been validated in Norway. SF-36 evaluates eight domains of health: physical functioning, role limitation due to physical problems, bodily pain, general perception of health, social functioning, role limitations due to emotional functioning, vitality and mental health. Items on each scale are summed to yield a score from 0-100. A higher score means better quality of life. A license from Quality Metric is used for scoring (License number QM051240). The eight domains are summarized into physical component summary scores and mental component summary scores.

  Feb 2022-Dec 2026

• Needs and Provision Complexity Scale

  Presence of health care needs. This is an interview that evaluates the needs for healthcare and social support services. It has two parts: Part A (Needs) is completed by the clinician to evaluate each patient's need for health and social care; and Part B (Gets) is to evaluate to which these needs are met through the services that have been provided, based on information provided by the patient and a close relative. Each part includes 15 items with a total scoring range of 0-50 covering low and high levels of needs. There are six subscales representing two domains: Health and personal care needs, and Social and support needs. This scale was developed in the UK for neurological conditions and has been translated and used in Norway.

  Feb 2022-Dec 2026

• Behavioral Rating Inventory of Executive Function- Adult Version

  Assessing cognitive problems. BRIEF-A is a measure of everyday executive functions using self-reports. It includes 75 items that assess nine aspects of executive functioning symptoms of everyday life. Raw scores are transformed into age-corrected T-scores. Higher T-scores mean better executive function.

  Feb 2022-Dec 2026

Secondary Outcomes (3)

• Short Physical Performance Battery;

  Feb 2022-Dec 2026

• The Hospital Anxiety and Depression Scale;

  Feb 2022-Dec 2026

• Three Factor Eating Questionnaire-R21

  Feb 2022-Dec 2026

Interventions

No intervention OTHER

No intervention

Eligibility Criteria

• Age: 16 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Individuals with BBS, age 16 years or older

You may qualify if:

• Individuals diagnosed with BBS (see below), age 16 years or older. BBS is characterized by six core features : rod-cone dystrophy (retinitis pigmentosa), polydactyly, obesity, genital anomalies, renal anomalies, and learning difficulties.
• Additional features include speech delay, developmental delay, diabetes mellitus, dental anomalies, congenital heart disease, brachydactyly (shortening of fingers/toes), ataxia, and anosmia/hyposmia (deficienct sense of smell). A minimum of four of the core features, or three core features and two additional features are required for the clinical diagnosis of BBS.

You may not qualify if:

• Individuals age \< 16 years, current severe illness or known diagnosis of autism.

Sponsors & Collaborators

• Oslo University Hospital: lead
• Lovisenberg Diakonale Hospital: collaborator
• Sykehuset Telemark: collaborator

Study Sites (1)

Oslo University Hospital

Oslo, 0373, Norway

Location

Related Publications (1)

• Rustad CF, Bragadottir R, Nordgarden H, Miller JU, Weedon-Fekjaer MS, Arfa S, Asten PM, Tveten K, von der Lippe C, Sigurdardottir S. Healthcare needs, care use and health status outcomes in adults with Bardet-Biedl syndrome: a cross-sectional study in Norway. BMJ Open. 2025 Apr 22;15(4):e095986. doi: 10.1136/bmjopen-2024-095986.

  PMID: 40262952 DERIVED

Biospecimen

Retention: SAMPLES WITH DNA

Blood tests will include renal-, liver-, bone-, lipid-, and endocrine profiles. EDTA blood samples will be sent to Telemark hospital for genetic testing, for individuals lacking molecular genetic confirmation of diagnosis.

MeSH Terms

Conditions

Bardet-Biedl Syndrome; Retinitis Pigmentosa; Obesity; Polydactyly; Cognition Disorders

Condition Hierarchy (Ancestors)

Hypothalamic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Eye Diseases, Hereditary; Eye Diseases; Ciliopathies; Abnormalities, Multiple; Congenital Abnormalities; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Genetic Diseases, Inborn; Retinal Dystrophies; Retinal Degeneration; Retinal Diseases; Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Limb Deformities, Congenital; Musculoskeletal Abnormalities; Musculoskeletal Diseases; Neurocognitive Disorders; Mental Disorders

Study Officials

• Charlotte von der Lippe, MD, PhD

  Oslo University Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: December 22, 2021
• First Posted: June 1, 2022
• Study Start: February 1, 2022
• Primary Completion: March 31, 2023
• Study Completion: March 31, 2023
• Last Updated: August 7, 2025

Record last verified: 2025-08

Locations

NO (1)