Genetic analysis of the ALMS1 gene in two families affected with Alstr?m syndrome / 中华眼底病杂志

Objective:To identify two pathogenic gene mutations in two families with Alstr?m syndrome (ALMS).Methods:A retrospective clinical study. Two patients and five family members from two Han families of ALMS diagnosed at Henan Eye Hospital from August 2020 to December 2021 were enrolled in this study. All participants underwent comprehensive ophthalmic examinations including best corrected visual acuity (BCVA), color test, slit-lamp, fundus biomicroscopy with slit lamp, fundus color photography, optical coherence tomography (OCT) and full-field electroretinography (ff-ERG) after the detailed history of the patient was taken. Five millilitres peripheral venous blood of each subject was collected, and the whole genome DNA was extracted. The pathogenic genes and mutation sites were identified using whole exome sequencing and the identified mutations were verified by Sanger sequencing. Mutation sites were analyzed via bioinformatics softwares.Results:Family one included one victim and two members and family two included one victim and three members. Proband in the first family was a four-year old boy whose chief complaint was poor vision along with photophobia since born, while proband in the second family was a 12-year old girl whose chief complaint was the same. The boy proband could not distinguish color, and both the anterior segment and fundus were normal. Ellipsoid zone of the boy was unclear in both eyes in OCT, and though rod system function decreased mildly-moderately in both eyes, the cone system function decreased severely in ff-ERG. The girl could not distinguish color as well, and the anterior segment was normal, though obvious pigmentary change could be seen in both retinas. The integrity of outer retinal bands was unclear in both eyes in OCT, and both cone and rod systems function decreased severely in both eyes in ff-ERG. Gene tests and bioinformatics analyze showed c.468dupT and c.10819C>T of ALMS1 gene in family one were novel mutations and c.10819C>T in family one and c.10831_10832del in family two were pathogenic mutations. Conclusions:M1, M2 and M3, M4 may be pathogenic gene variants in family 1 and family 2, respectively. The compound heterozygous mutation, c.468dupT and c.10819C>T of ALMS1 gene was a novel mutation.

Analysis of the ocular clinical features and pathogenic genes in patients with Alstr?m syndrome / 中华眼底病杂志

Objective:To observe and analyze the ocular clinical features and pathogenic genes of Alstr?m syndrome (ALMS).Methods:A retrospective clinical study. From October 2020 to July 2022, 3 patients and 5 normal family members from 2 families affected with ALMS who visited in the Ophthalmology Department of Henan Children's Hospital were enrolled in the study. These 2 families were without blood relationship. The medical history and family history were inquired. Best corrected visual acuity (BCVA), fundus color photography, full-field electroretinogram (ERG), frequency domain optical coherence tomography (OCT) and systemic examination were performed. 3 ml peripheral venous blood of patients and their family members were collected, and the whole genomic DNA was extracted. The second generation sequencing analysis was performed on these members. The suspected pathogenic mutation sites were verified by Sanger, and the pathogenicity of the gene mutation sites were determined by bioinformatics analysis.Results:Three patients from two families all developed nystagmus and photophobia in infancy. In the family 1, the BCVA of both eyes of the proband was no light perception. The fundus examination revealed vascular attenuation and retinal pigment abnormality. OCT showed retinal thinning, loss of photoreceptor layer and atrophy of the retinal pigment epithelium layer. ERG examination showed extinguished. The BCVA of the proband’s younger brother was 0.04 in the right eye and 0.02 in the left eye. The fundus examination revealed vascular attenuation but the pigment distribution was roughly normal. OCT showed blurred photoreceptor layers in both eyes. ERG examination showed extinguished. Two patients developed sensorineural deafness, obesity, acanthosis nigricans, insulin resistance/diabetes, and abnormal liver function. In addition, the proband also had left heart enlargement, hyperlipidemia and abnormal kidney function. The results of genetic testing showed that the proband and his younger brother had compound heterozygous mutations in exon 8 (c.1894C>T/p.Gln632*, M1) and exon 10 (c.9148_9149delCT/p.Leu 3050 Leufs*9, M2) of ALMS1, which were both known mutations. The father of the proband was a carrier of M1 and the mother of the proband was a carrier of M2. The proband of the family 2 had a normal fundus at 23 months old. The amplitude of ERG b wave under the stimulation of the dark adaptation 0.01 and a, b wave under the stimulation of dark adaptation 0.3 were all mild reduced. The amplitude of ERG a, b wave under the stimulation of the light adaptation 0.3 was severity decreased. At 4 years old, the BCVA was 0.01 in the right eye and 0.05 in the left eye. The fundus examination revealed vascular attenuation and bilateral blunted foveal reflex. In addition to severely diminished of a, b wave under the stimulation of dark adaptation 0.3, the rest showed extinguished. There were no systemic abnormalities. The results of genetic testing showed that the proband had compound heterozygous mutations in exon 11 (c.9627delT/p.Pro3210Glnfs*22, M3) and exon 5 (c.1089delT/p.Asp364Ilefs*13, M4) of ALMS1, which were both novel mutations. The father of the proband was a carrier of M3 and the mother of the proband was a carrier of M4. Conclusions:Nystagmus and photophobia are often the first clinical manifestations of ALMS. In the early stage, the fundus can be basically normal. As the disease progresses, the fundus examination reveals vascular attenuation and retinal pigment abnormality, and the reflection of the fovea is unclear. OCT shows the photoreceptor cell layers are blurred or even lost. The final ERG is extinguished. M1, M2, and M3, M4 compound heterozygous mutations may be the pathogeny for family 1 and family 2, respectively.

Introduction and interpretation of European clinical management guidelines for Alstr?m syndrome in 2020 / 中华实用儿科临床杂志

Alstr?m syndrome is a rare multisystem genetic disease caused by mutations in the ALMS1 gene.Both of its clinical diagnosis and treatment are very difficult.In 2020, the Consensus Clinical Management Guidelines for Alstr?m Syndrome, developed with the participation of many countries, was published in the Orphanet Journal of Rare Diseases.A systematic literature review on Alstr?m syndrome of the last 45 years until October 2019 was carried out and then the clinical management guideline for Alstr?m syndrome was proposed.In this report, the contents of the 2020 European guideline for Alstr?m syndrome would be introduced briefly with appropriate interpretation in order to provide reference.

Effects of long non-coding RNA ALMS1-IT1 on the proliferation and migration of colorectal cancer cells via regulating the expressions of miRNA-889-3p and ATAD2 / 肿瘤研究与临床

Objective:To investigate the expression of long non-coding RNA (lncRNA) ALMS1-IT1 in colorectal cancer tissues and the molecular mechanism of its effect on the proliferation and migration of colorectal cancer HT-29 cells in vitro.Methods:The cancer tissue specimens and paracancerous tissue (>5 cm from the edge of the tumor) specimens were collected from 40 colorectal cancer patients who were diagnosed by pathological examination after surgical resection in Hubei 672 Orthopedic Hospital of Integrated Traditional Chinese and Western Medicine from July 2018 to November 2020. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression level of ALMS1-IT1 in colorectal cancer tissues and paracancerous tissues, when the relative expression of ALMS1-IT1 was higher than or equal to its median relative expression, ALMS1-IT1 was highly expressed, and the correlation of ALMS1-IT1 expression with the clinicopathological characteristics of patients was analyzed. HT-29 cells were infected with the empty lentivirus and the lentivirus carrying the ALMS1-IT1 silence sequence, and named control group and si-ALMS1-IT1 group. qRT-PCR was used to detect the expression of ALMS1-IT1 in the two groups of HT-29 cells. CCK-8 method and Transwell experiment were used to detect the proliferation and migration ability of the two groups of HT-29 cells. The starBase v2.0 online database was used to predict ALMS1-IT1 interacting molecules, and qRT-PCR and Western blot were used to detect the expression of these molecules.Results:The relative expression of ALMS1-IT1 in colorectal cancer tissues was higher than that in paracancerous tissues (4.54±0.61 vs. 1.19±0.31, t = 34.89, P < 0.01). The median relative expression of ALMS1-IT1 in cancer tissues of 40 patients was 2.93, and the high expression rate of ALMS1-IT1 was 50.0% (20/40). The high expression rate of ALMS1-IT1 in cancer tissues of TNM stage Ⅲ patients was higher than that in TNM stage Ⅰ-Ⅱ patients, the high expression rate of ALMS1-IT1 in poorly-differentiated patients was higher than that in well- and moderately-differentiated patients, and the high expression rate of ALMS1-IT1 in patients with lymph node metastasis was higher than that in patients without lymph node metastasis (all P < 0.01). The cell proliferation capacity (absorbance value) of HT-29 cells in the si-ALMS1-IT1 group after cultured for 2, 3, 4, and 5 days was lower than that in the control group (all P < 0.05). The number of cell migration at 24 h in HT-29 cells of the si-ALMS1-IT1 group was less than that of the control group (45±7 vs. 112±18, t = 3.45, P < 0.05). Using starBase v2.0 online database to predict that the target gene of ALMS1-IT1 may be miRNA-889-3p (miR-889-3p), and the target gene of miR-889-3p may be ATAD2. Compared with the control group, the relative expression of miR-889-3p in HT-29 cells of the si-ALMS1-IT1 group increased (4.24±0.46 vs. 1.01±0.11, t = 6.81, P < 0.01). Compared with the control group, ATAD2 mRNA ( P < 0.01) and protein expression levels in the si-ALMS1-IT1 group were reduced. Conclusions:ALMS1-IT1 is highly expressed in colorectal cancer tissues, and the ALMS1-IT1 expression is related to the TNM stage, degree of tumor differentiation and lymph node metastasis of patients. Down-regulation of ALMS1-IT1 in vitro may inhibit the proliferation and migration of colorectal cancer HT-29 cells by regulating the miR-889-3p-ATAD2 axis. ALMS1-IT1 may be a therapeutic target for colorectal cancer.

Progress in pathogenesis, diagnosis, and treatment of Alstrom syndrome / 国际儿科学杂志

Alstrom syndrome (ALMS) is a rare autosomal recessive disorder involving multiple systems.The main clinical manifestations include nystagmus,hearing loss,obesity,insulin resistance,type 2 diabetes,dilated cardiomyopathy,etc.Primary cilia are key organelles.ALMS is classified as a ciliopathy,mainly related to the mutation of ALMS1 gene which affects cilia function,but the specific mechanism remains unclear.At present,the diagnosis of ALMS mainly relies on clinical manifestations and gene sequencing.There are no specific and effective treatment methods except for symptomatic treatment,but early diagnosis and intervention can delay disease progression and improve patients' quality of life.This article reviews recent advances in the pathogenesis,diagnosis,and treatment of ALMS.

Progress in pathogenesis, diagnosis, and treatment of Alstrom syndrome / 国际儿科学杂志

Alstrom syndrome(ALMS)is a rare autosomal recessive disorder involving multiple systems.The main clinical manifestations include nystagmus, hearing loss, obesity, insulin resistance, type 2 diabetes, dilated cardiomyopathy, etc.Primary cilia are key organelles.ALMS is classified as a ciliopathy, mainly related to the mutation of ALMS1 gene which affects cilia function, but the specific mechanism remains unclear.At present, the diagnosis of ALMS mainly relies on clinical manifestations and gene sequencing.There are no specific and effective treatment methods except for symptomatic treatment, but early diagnosis and intervention can delay disease progression and improve patients′ quality of life.This article reviews recent advances in the pathogenesis, diagnosis, and treatment of ALMS.

Alstrom syndrome in children:a case report and literature review / 临床儿科杂志

Objective To analyze the clinical feature, diagnosis and treatment of Alstrom syndrome. Method The clinical data of a case of Alstrom syndrome and the result of her ALMS1 sequencing by the two generation sequencing were retrospectively reviewed. Results The 12 year and 10 month old female suffered from dilated cardiomyopathy, obesity, optic nerve diseases, sensorineural hearing loss, high blood glucose and irregular menstruation since one month of birth. Laboratory examination showed she had high testosterone level, hyperglycemia, hyperlipidemia and fatty liver. High-throughput sequencing confirmed there was ALMS1 gene mutation which includes hybrid frameshift mutations of c.5418delC and p.Y1807Tfs*23, and heterozygous nonsense mutation of c.10549C>T and p.Q3517*, and c.5418delC was a new variation reported for the first time. Conclusion Alstrom syndrome is an autosomal recessive genetic disease, which is characterized by multiple organ dysfunction and metabolic syndrome, and can be diagnosed by gene detection.

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.