Source – A unique description of the study from which the record was extracted, the list of all the studies with links can be found in References.

Family – A unique randomly generated family identifier.

Source ID – ID or any information that allows the identification of the particular patient in the original study.

Gene – A BBS gene with a BBS-causative mutation.

Nucl. change – Nucleotide change describing the causative mutation in a BBS patient. Allele 1/allele 2 indicate if the patient carries two similar mutations (being a homozygote) or if there is a different mutation in each allele (compound heterozygote). See Sequence Variant Nomenclature for more information about the mutation notation.

Protein change – Protein change describing the causative mutation in a BBS patient. See Sequence Variant Nomenclature for more information about the mutation notation.

TOM – “Type Of Mutation” in allele 1/allele 2. MS – Missense mutations (missense substitutions, deletions of 3, 6 or 9 nucleotides), cLOF – assumed complete loss of function mutation (frameshift mutations, nonsense substitutions, large deletions and splicing defects).

Additional mutations – Field containing additional mutations and variations identified in ciliopathy-related genes alongside the BBS causative mutation. The pathogenicity of these mutations is usually unknown.

Sex – M for male, F for female.

Age group – Age at the BBS diagnosis/Age of the clinical assessment grouped into the following ranges: 0-9 years of age, 10-19 years of age, 20-29 years of age, 30-39 years of age, 40+ years of age.

Age – Age at the diagnosis/Age of the clinical assessment in years.

RD (Retinal dystrophy)* – rod-cone/cone-rod dystrophy/degeneration, retinitis pigmentosa, Leber congenital amaurosis, night blindness, pigmentary retinopathy, tapetoretinal degeneration, ocular nerve atrophy, poor night vision

OBE (Obesity)* – BMI > 25 for adults and children older than 15 years of age OR weight > 95 quantile for children up to 15 years of age, medical history of obesity

PD (Polydactyly)* – pre-, meso-, post-axial polydactyly

CI (Cognitive impairment)* – IQ < 70, learning difficulties, mental retardation, reduced intelligence

REP (Reproductive system anomalies)* – males: micropenis, hypospadias, cryptorchidism, hypogonadism, females: primary amenorrhea, vaginal atresia/agenesis, urigenital sinus malforation, vaginal agenesis, malformed/infantile/bicornate/abnormally positioned uterus, uterine leiomyoma, hydrometrocolpos, polycystic ovary syndrome, ovarian cysts/tumour, both: abnormal/ambigous genitalia

REN (Renal anomalies)* – chronic kidney disease, polycystic kidney disease/cystic kidney/renal cysts, renal failure, renal dysplasia, renal transplant, renal cortical atrophy, dilatation of renal pelvis, horseshoe kidney, enlarged/small kidneys, hydronephrosis, impaired renal function, kidney agenesis with milder renal symptoms, kidney stone, nephrolithiasis, nephronophthisis, fetal lobulation, eGFR < 60

HRT (Heart anomalies)* ­– congenital cardiac anomaly, congenital heart disease, atrial septal defect, heart anomalies

LIV (Liver anomalies)* – non-alcoholic fatty liver, hepatomegaly, polycystic liver/liver cysts, liver steatosis, liver impairment, abnormal liver structure, abnormal liver function

DD (Developmental delay)* ­– motor delay, growth delay, general developmental delay, psychomotor delay, delayed sexual development

* In all the above phenotypes, the phenotype was scored as “1” (positive) if any of the conditions listed below was reported to be present in the patient. However, due to the different methodology of the source studies, we can’t guarantee that a patient scored with “0” was tested for all the listed conditions.

The following conditions were not scored as positive: retinal dystrophy – ocular phenotypes non-related to retina; polydactyly – brachydactyly, syndactyly, clinodactyly; reproductive system anomalies – gynaecomastia, recurrent urinary tract infections, irregular menstruation.

Ethnicity – Geographic or ethnic origin of the patient.

Notes – Any useful notes, but mostly information about merging phenotypes of one patient from multiple studies.