Bardet-Biedl syndrome: a case report / 中华肾脏病杂志

Bardet-Biedl syndrome (BBS) is an autosomal recessive hereditary rare disease with high heterogeneity in clinical phenotypes, which can affect multiple systems, such as six fingers/digits deformity, mental impairment, retinopathy, polycystic kidney, etc, and is easily diagnosed according to a single system disease, resulting in misdiagnosis. The paper reports a case of BBS, diagnosed with "renal cyst, developmental delay, chondrosis, and left foot hexadactylism" at 5 years old, "anemia, renal insufficiency, distal renal tubule poisoning, renal osteodystrophy" at 7 years old. At 10 years old, the patient received hemodialysis treatment for uremia. Cloudy vision appeared in both eyes at 14 years old. Because of the prominent manifestation of kidney damage, the patient was misdiagnosed as "polycystic kidney" for a long time, and other systemic damages were ignored. The result of gene sequencing showed that chromosome 16 NM_031885.5 exon17 had one homozygous nonsense mutation. Therefore, the patient was accurately diagnosed as BBS. This paper is the first report of BBS in Li nationality in China. The relevant literature of BBS were reviewed to strengthen clinicians' understanding of the disease and improve patients' prognosis.

Síndrome de Bardet Biedl: a propósito de un caso / Bardet Biedl syndrome: a case report

El síndrome de Bardet Biedl es un síndrome genético de herencia autosómica recesiva con compromiso multisistémico y gran variabilidad en su presentación clínica; son características la obesidad, la polidactilia, el hipogonadismo y las alteraciones renales, visuales y cognitivas. Pertenece a las llamadas ciliopatías. El diagnóstico es clínico y puede ser confirmado por estudios genéticos. No existe un tratamiento específico de la patología; se requiere un abordaje multidisciplinario. Se presenta el caso de una paciente de 13 años con obesidad e hiperfagia, diabetes tipo 2, hipotiroidismo, polidactilia, alteraciones del aprendizaje y alteraciones visuales. Se le realizó un panel genético para obesidad en el que se detectaron dos variantes heterocigotas patológicas en el gen BBS2.

Bardet Biedl syndrome is an autosomal recessive ciliopathie. It is a pleiotropic disorder characterised by retinal dystrophy, renal dysfunction, polydactyly, obesity, cognitive deficitand hypogenitalism. Diagnosis is based on clinical features. Molecular genetic testing is available. There is no specific treatment, a multidisciplinary approach is required. We report the case of a 13-year-old female patient with obesity and hyperphagia, type 2 diabetes, hypothyroidism, polydactyly,cognitive deficit and visual impairment. A multigenic panel allowed the identification of two heterozygous pathogenic variants in the BBS2 gene.

Retinitis pigmentosa in Laurence-Moon-Bardet-Biedl syndrome in India: Electronic medical records driven big data analytics: Report II

Purpose: To describe the clinical presentation and demographic distribution of retinitis pigmentosa (RP) in Laurence–Moon–Bardet–Biedl (LMBB) syndrome patients. Methods: This is a cross?sectional observational hospital?based study wherein 244 patients with RP in LMBB syndrome presenting to our hospital network between March 2012 and October 2020 were included. An electronic medical record database was used for data retrieval. Results: There were 244 patients in total, with a hospital?based prevalence rate of 0.010% or 1000/100,000 population. The mean and median age of patients was 15.22 ± 7.56 and 14 (IQR: 10–18.5) years, respectively, with the majority being in the age group of 11–20 years (133/244 patients; 54.50%). Males were more commonly affected (164 patients; 67.21%), and the majority (182 patients; 74.59%) were students. All 244 patients (100%) complained of defective central vision at presentation. More than one?fourth of the patients had severe visual impairment to blindness at presentation. Prominent retinal feature at presentation was diffuse or widespread retinal pigment epithelial degeneration in all patients. Conclusion: Patients with RP in LMBB syndrome present mainly in the first to second decade of life with severe visual acuity impairment to blindness early in life. It is important to rule out LMBB syndrome in early?onset RP with central visual acuity impairment. On the contrary, all patients diagnosed or suspected with LMBB syndrome systemic features at physician clinic should also be referred for ophthalmic evaluation, low vision assessment, rehabilitation, and vice versa

Bardet-Biedl syndrome in a female due to a novel compound heterozygous mutations in BBS10 gene: One case report and literature review / 中华内分泌代谢杂志

Bardet-Biedl syndrome (BBS) is a rare and highly heterogeneous autosomal recessive disease caused by ciliary structure abnormality or dysfunction. Here we report a case of a 23-year-old woman who was diagnosed with BBS with a rare BBS10 gene mutation. Literature review was performed with a focus to outline treatment and management plans for patients with this rare and potentially dangerous disease.

BARDET BIEDL SYNDROME IN PREGNANCY A CASE REPORT

Bardet Biedl Syndrome (BBS) is a rare idiopathic autosomal recessive disorder which affects multiple organs and organ systems. In India less than 15 cases have been reported so far. We present case of 41 year old third gravida who presented at 17 weeks of gestation. She had a suspicious history of delayed milestones in the previous child and ultrasound findings of echogenic kidneys, bilateral talipes, and polydactyly. Index child evaluation showed type-6 variant of BBS. Amniocentesis in the present pregnancy showed the same mutation in the fetus. The couple decided on termination of t pregnancy.

A rare case of polydactyly with multiple defects

Bardet-Biedl Syndrome (BBS) is a very rare genetically heterogenous disorder. Here is a case of 27 yr. old obese male presented with acute gastroenteritis with shock in our department. He had polydactyly in both upper limb and left lower limb, blindness since childhood, with difficult in learning and delayed onset of milestones. Patient抯 sibling (younger brother 20-year-old) also had same problems since childhood and one female baby died within few days of birth. He was having single testis. Patient was managed conservatively. The available literature on this syndrome was reviewed.

Bardet-Biedl syndrome protein-8 is involved in flagellar membrane protein transport in Chlamydomonas reinhardtii / 生物工程学报

Cilia and flagella on eukaryotic cells are polarized organelles extending from the surfaces of cells, which participate not only in cell motility, but also in signal transduction and other processes. Structural or functional abnormalities of cilia can cause various human diseases, termed ciliopathies. Bardet-Biedl syndrome (BBS) is a ciliopathic human genetic disorder, and the pathogenesis is that mutated BBS genes result in abnormal cilia function. In order to study the pathogenic genes BBS8, we screened bbs8 mutant in Chlamydomonas reinhardtii and did a lot of physiology and biochemistry experiments. We affirmed that BBS8 protein was a cilia protein and had specific localization in the basal body by immunofluorescence (IF). The bbs8 mutant lost photokinesis, and it was defective in flagella shortening with drug induction. The results of silver staining and mass spectrometric analysis showed aberrant accumulation of flagellar proteins in the mutant flagella. We concluded that the BBS8 protein plays a significant role in flagellar membrane proteins transport, and the BBS8 protein might mediate retrograde transport to exert physiological function in the process.

Variante patogénica homocigótica del gen BBS10 en un paciente con síndrome de Bardet-Biedl / A pathogenic homozygous variant of the BBS10 gene in a patient with Bardet Biedl syndrome

Resumen El síndrome de Bardet-Biedl es una enfermedad hereditaria, autosómica recesiva, con gran heterogeneidad de locus, que pertenece a las denominadas ciliopatías, denominadas así por la deficiencia funcional presente y porque las proteínas afectadas se localizan en el cilio primario. El síndrome afecta múltiples sistemas, con compromiso visual, renal, cognitivo, esquelético y gonadal, y obesidad. Este síndrome presenta una gran variabilidad intrafamiliar e interfamiliar. Se presenta el caso clínico de un paciente adolescente con diagnóstico de síndrome de Bardet-Biedl, así como su manejo, los resultados de la secuenciación de 22 genes y el análisis actualizado de la literatura médica. Se recopiló la información clínica y, previo consentimiento informado, se hizo la prueba de panel de secuenciación multigénica de los genes implicados. El paciente es hijo de la unión de personas consanguíneas. Fue el primer afectado en la familia y presentaba polidactilia posaxial, obesidad, micropene, retinitis pigmentaria y dificultades de aprendizaje. En el panel multigénico, se identificó la variante patogénica homocigótica c.39_46del en el gen BBS10 y otras variantes de genes BBS asociadas con la obesidad. Dado que el síndrome de Bardet-Biedl es una enfermedad huérfana rara, interpretar el pleiotropismo y la heterogeneidad de locus y de alelos, constituye un reto. La confirmación molecular permite el manejo adecuado de los pacientes, así como el seguimiento y el asesoramiento genético apropiados.

Abstract The Bardet-Biedl syndrome is an autosomal recessive hereditary disorder with vast locus heterogeneity that belongs to the so-called ciliopathies, whose proteins are localized in the primary cilia and present functional deficiency. The multisystemic features of the disease include ocular, renal, cognitive, skeletal, as well as gonadal involvement and obesity, among others, with high inter- and intrafamilial variability. We describe the clinical case of an adolescent male patient with Bardet-Biedl syndrome, including the approach, the results from a 22-gene sequencing panel, and the analysis of updated scientific literature. We collected the clinical data of the patient and, after obtaining the informed consent, we conducted a multigenic sequencing panel oriented to known implicated genes. The patient was born to consanguineous parents and was the first affected member of the family. He presented with postaxial polydactyly, obesity, micropenis, retinitis pigmentosa, and learning disability. The multigenic panel allowed the identification of the homozygous pathogenic variant c.39_46del in the BBS10 gene and in other BBS genes variants associated with obesity. As the Bardet-Biedl syndrome is a rare disease, it is challenging to interpret its pleiotropism and gene/allelic heterogeneity. Its confirmation by molecular tests allows an adequate approach, follow-up, and genetic counseling of the patient and the family.

Screening for mutation hotspots in Bardet–Biedl syndrome patients from India

Background & objectives: Bardet–Biedl syndrome (BBS) is a genetically heterogeneous autosomal recessive disorder characterized by multiple organ defects involving retina, kidney, liver and brain. Disease-causing mutations in BBS genes narrowed down by homozygosity mapping in small consanguineous and non-consanguineous pedigrees were reported in 80 per cent of the study population. This study was aimed to screen these genes (BBS3, BBS10) and specific exons of BBS genes (BBS1, BBS5, MKKS, BBS9, BBS11 and BBS12) for recurrent mutations in a selected sample of BBS patients. Methods: The recurrent mutations in BBS genes were screened in the BBS affected individuals by PCR based direct sequencing. The pathogenicity of the observed mutations were confirmed by co-segregation analysis, screening of healthy unrelated controls and in silico analysis. Results: In the 64 BBS patients (44 males, 20 females) were studied, mutations were predominant in BBS10 and ARL6 genes; the c.272T>C; p.(I91T) mutation in ARL6 gene was a recurrent mutation. One novel non-sense mutation c.425T>G; p(L142*) was obtained in BBS5 gene (family BSI-31). Interpretation & conclusions: BBS10 gene mutations clustered in exon 2 of the gene suggesting the exon as a probable hotspot for mutations in Indian population. A cost- and time-effective strategy for the molecular diagnosis of BBS was designed based on these results.

Novel mutations in the BBS12 gene of two Chinese Bardet-Biedl syndrome pedigrees / 中华肾脏病杂志

Objective To Summarize and review the clinical data of two Bardet-Biedl syndrome (BBS) children so as to improve our understanding of the disease.Methods Clinical data of two BBS pedigree were collected.Gene analysis was performed by exon capture and next-generation sequencing,validated using Sanger sequencing.Results Both cases were male,Han nationality,born with polydactyly and had rapid weight gain after birth.They went to see the pediatric endocrinologist due to obesity,and found increased serum creatinine level,so were referral to pediatric nephrologists.Case one was further diagnosed rod-cone dystrophy,bilateral renal multiple cysts (chronic kidney disease,stage 4),atrial septal defect,mental retardation,hypertension and abnormal hearing.Two novel heterozygous compound mutation of BBS12 gene [c.1604T ＞ G (p.V535G) paternal,c.173delA (p.E58Efs*5) maternal] and one known BBS4 missense mutation (paternal) were detected.Case two was detected multiple cysts in kidneys by ultrasound in fetal phase.He was suspected to have autism.He had small penis,hypertension and renal injury (chronic kidney disease,stage 3).Two novel heterozygous compound mutation of BBS12 gene [c.1783T ＞ C (p.W595R) paternal,c.1749_1750delA (p.R584Dfs*54) maternal] were detected.All mutations were predicted to be harmful.Conclusions BBS is a rare disease.It is difficult to be diagnosed at early age.Polydactyly and obesity can be the early two symptoms for seeing doctors.Few cases have been diagnosed upon gene analysis.In this study,the mutation of BBS12 in Chinese and 4 novel mutations in BBS12 with severe renal injury are reported for the first time.It will extend the spectrum of BBS gene mutations.

Bardet–Biedl syndrome: Genetics, molecular pathophysiology, and disease management.

Primary cilia play a key role in sensory perception and various signaling pathways. Any defect in them leads to group of disorders called ciliopathies, and Bardet–Biedl syndrome (BBS, OMIM 209900) is one among them. The disorder is clinically and genetically heterogeneous, with various primary and secondary clinical manifestations, and shows autosomal recessive inheritance and highly prevalent in inbred/consanguineous populations. The disease mapped to at least twenty different genes (BBS1-BBS20), follow oligogenic inheritance pattern. BBS proteins localizes to the centerosome and regulates the biogenesis and functions of the cilia. In BBS, the functioning of various systemic organs (with ciliated cells) gets deranged and results in systemic manifestations. Certain components of the disease (such as obesity, diabetes, and renal problems) when noticed earlier offer a disease management benefit to the patients. However, the awareness of the disease is comparatively low and most often noticed only after severe vision loss in patients, which is usually in the first decade of the patient’s age. In the current review, we have provided the recent updates retrieved from various types of scientific literature through journals, on the genetics, its molecular relevance, and the clinical outcome in BBS. The review in nutshell would provide the basic awareness of the disease that will have an impact in disease management and counseling benefits to the patients and their families.

Identification of Two Cases of Ciliopathy-Associated Diabetes and Their Mutation Analysis Using Whole Exome Sequencing

BACKGROUND: Alstrom syndrome and Bardet-Biedl syndrome are autosomal recessively inherited ciliopathies with common characteristics of obesity, diabetes, and blindness. Alstrom syndrome is caused by a mutation in the ALMS1 gene, and Bardet-Biedl syndrome is caused by mutations in BBS1-16 genes. Herein we report genetically confirmed cases of Alstrom syndrome and Bardet-Biedl syndrome in Korea using whole exome sequencing. METHODS: Exome capture was done using SureSelect Human All Exon Kit V4+UTRs (Agilent Technologies). HiSeq2000 system (Illumina) was used for massive parallel sequencing. Sanger sequencing was used for genotype confirmation and familial cosegregation analysis. RESULTS: A 21-year old Korean woman was clinically diagnosed with Alstrom syndrome. She had diabetes, blindness, obesity, severe insulin resistance, and hearing loss. Whole exome sequencing revealed a nonsense mutation in exon 10 of ALMS1 (c.8776C>T, p.R2926X) and a seven base-pair deletion resulting in frameshift mutation in exon 8 (c.6410_6416del, p.2137_2139del). A 24-year-old Korean man had Bardet-Biedl syndrome with diabetes, blindness, obesity, and a history of polydactyly. Whole exome sequencing revealed a nonsynonymous mutation in exon 11 of the BBS1 gene (c.1061A>G, p.E354G) and mutation at the normal splicing recognition site of exon 7 of the BBS1 gene (c.519-1G>T). CONCLUSION: We found novel compound heterozygous mutations of Alstrom syndrome and Bardet-Biedl syndrome using whole exome sequencing. The whole exome sequencing successfully identified novel genetic variants of ciliopathy-associated diabetes.

Report of four cases of Bardet-Biedl syndrome / Relato de quatro casos da síndrome de Bardet-Biedl

Bardet-Biedl syndrome is rare. Although its diagnosis depends on cardinal clinical manifestations which appear in childhood, we report four cases of Bardet-Biedl syndrome lately diagnosed in a dialysis center. Three cases were diagnosed in end-stage renal disease patients when they started maintenance hemodialysis, and one case was diagnosed through screening among hemodialysis patients' relatives. Although pediatricians have more opportunity to diagnose the syndrome, nephrologists are important during the treatment, since renal failure is the main cause of death among Bardet-Biedl syndrome patients. Moreover, late diagnosis of the syndrome among patients with end-stage renal disease can help to detect new cases through the screening among hemodialysis patients' relatives.

A síndrome de Bardet-Biedl é rara. Embora seu diagnóstico seja baseado em manifestações cardinais que aparecem na infância, relatamos quatro casos de síndrome de Bardet-Biedl diagnosticados tardiamente em uma unidade de diálise. Três casos foram diagnosticados em pacientes com doença renal crônica terminal quando iniciaram hemodiálise de manutenção, e um caso diagnosticado por meio de rastreamento dos parentes dos casos em diálise. Embora pediatras tenham mais oportunidade para diagnosticar a síndrome, nefrologistas são importantes durante o tratamento, já que a insuficiência renal é a principal causa de óbito entre os pacientes com síndrome de Bardet-Biedl. Além disso, o diagnóstico tardio da síndrome entre pacientes com doença renal crônica terminal pode ajudar a detecção de casos novos por meio do rastreamento de parentes dos pacientes em hemodiálise.

Two siblings with Bardet-Biedl syndrome caused by mutations in BBS10: the first case identified in Korea

Bardet-Biedl syndrome (BBS) is a rare ciliopathy generally inherited with an autosomal recessive pattern. BBS is characterized by 6 primary features namely retinal dystrophy, obesity, postaxial polydactyly, renal dysfunction, learning difficulties, and hypogonadism and a wide range of secondary features. To date, mutations in 16 genes have been identified as causative factors for BBS. Among them, the BBS1 and BBS10 genes are major disease-causing genes, and each of these gene mutations presents in more than 20% of all BBS patients. Genotype-phenotype correlations have not been observed in BBS, and there can be phenotypic overlap between BBS and other ciliopathies. In Korea, no molecular, genetically confirmed case of BBS has been reported to date. Herein, we describe the case of the first Korean siblings with BBS resulting from 2 BBS10 gene mutations who showed typical clinical phenotypes, including retinal dystrophy, obesity, intellectual disability, cystic tubular disease, and postaxial polydactyly.

Bardet-Biedl Syndrome – A Rare Cause of Cardiomyopathy.

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive condition characterized by retinitis pigmentosa, polydactyly, obesity, learning disabilities, hypogonadism and renal anomalies. Cardiomyopathy in association with BBS has previously being reported only twice in literature. We report a case of a patient presenting with features of cardiomyopathy, who was subsequently diagnosed to have BBS.

Bardet-Biedl syndrome: A rare case report from North India.

The Bardet-Biedl syndrome (BBS) is a rare ciliopathic human autosomal-recessive disorder, affecting multiple organ systems. Less than 15 cases have been reported from India. The authors present a classical case of BBS presenting to dermatology outpatient with hypogonadism and features such as marked central obesity, retinal dystrophy, polydactyly, structural renal abnormalities and mental retardation, along with a brief review of the literature. This case exemplifies the need for multidisciplinary management in such cases.

A Miao pedigree of Bardet-Biedl syndrome in Yunnan province and their gene reservation / 中华内分泌代谢杂志

Objective To observe the features of a rare Miao pedigree of Bardet-Biedl syndrome in Yunnan province and to reserve its gene. Methods Three patients of this pedigree were reported. Their clinical and biochemical features were compared with those of the other pedigree members. Lymphocytes from main members of this pedigree were collected and transformed with cyclosporine A methods. Immortalized B lymphocyte strains were checked by means of chromosome karyotype analysis. Results Patients of this pedigree demonstrated typical clinical characteristics of this syndrome with increased body weight, blood pressure, fasting glucose, and lipoprotein(a)as compared with the other pedigree members(P＜0. 05). The chromosome karyotype of the lymphocytes before and after transformation was kept consistent. Conclusions Patients of this Miao pedigree showed typical clinical characteristics of this syndrome as well as abnormal metabolic features. Immortalized B lymphocyte strains with their genetic information were set successfully.

A case of McKusick-Kaufman syndrome / 소아과

McKusick-Kaufman syndrome (MKS) is an autosomal recessive multiple malformation syndrome characterized by hydrometrocolpos (HMC) and postaxial polydactyly (PAP). We report a case of a female child with MKS who was transferred to the neonatal intensive care unit of Seoul National University Children's Hospital on her 15th day of life for further evaluation and management of an abdominal cystic mass. She underwent abdominal sonography, magnetic resonance imaging, genitography and cystoscopy which confirmed HMC with a transverse vaginal septum. X-rays of the hand and foot showed bony fusion of the left third and fourth metacarpal bones, right fourth dysplastic metacarpal bone and phalanx, right PAP and hypoplastic left foot with left fourth and fifth dysplastic metatarsal bones. In addition, she had soft palate cleft, mild hydronephroses of both kidneys, hypoplastic right kidney with ectopic location and mild rotation, uterine didelphys with transverse vaginal septum and low-type imperforated anus. She was temporarily treated with ultrasound-guided transurethral aspiration of the HMC. Our patient with HMC and PAP was diagnosed with MKS because she has two typical abnormality of MKS and she has no definite complications of retinal disease, learning disability, obesity and renal failure that develop in Bardet-Biedl syndrome, but not in MKS until 33 months of age. Here, we describe a case of a Korean patient with MKS.

Pigmentary retinopathy due to Bardet-Biedl syndrome: case report and literature review / Retinopatia pigmentar devido a síndrome de Bardet-Biedl: relato de caso e revisão da literatura

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder with clinical and genetic heterogeneity. This syndrome was first described by Laurence and Moon in 1866 and additional cases were described by Bardet and Biedl between 1920 and 1922. The main features are obesity, polydactyly, pigmentary retinopathy, learning disabilities, various degrees of intellectual impairment, hypogonadism, and renal abnormalities. Bardet-Biedl syndrome is both phenotypically and genetically heterogeneous. Clinical diagnosis is based on the presence of 4 of the 5 cardinal features. The authors present a typical case of pigmentary retinopathy due to Bardet-Biedl syndrome and made a brief commentary about the disease's cardinal manifestations.

A síndrome de Bardet-Biedl (BBS) é uma desordem autossômica recessiva rara, com heterogeneidade clínica e genética. Esta síndrome foi descrita pela primeira vez por Laurence e Moon em 1866 e outros casos foram descritos por Bardet e Biedl entre 1920 e 1922. As principais características são obesidade, polidactilia, retinopatia pigmentar, dificuldades de aprendizagem, graus de deficiência intelectual diversos, hipogonadismo e anomalias renais. Síndrome de Bardet-Biedl é fenotipicamente e geneticamente heterogêneos. O diagnóstico clínico baseia-se na presença de quatro dos cinco sinais principais da síndrome. Os autores apresentam um caso típico de retinopatia pigmentar devido à síndrome de Bardet-Biedl e fazem uma breve revisão sobre as manifestações da síndrome com especial atenção à retinopatia pigmentar.

The meta-analysis of Laurance-Moon-Bardet-Biedl syndrome / 中国实用内科杂志

Objective To deepen the clinicians' impression on the Laurance-Moon-Bardet-Biedl syndrome(LMBBS),we made a summary in the incidence and clinical manifestations of the disease in China comparing with foreigners.Methods We made evidence-based meta-analysis about the 2 cases reports in 1987 and 2003 in our hospital and literature review of 462 cases in foreign countries and 94 cases in China.Results LMBBS patients,with more frequency of consanguinity and family history,retinal dystrophy,mental retardation,obesity,polydactyly,hypogenitalism,often had many complicated and variable clinical manifestations.Conclusion To avoid intrafamiliy marriage would reduce the incidence rate.The diagnostic criteria and ascertainment methods introduced recently do benefit the early diagnosis in their childhood period.