Anatomical Characteristics and Potential Gene Mutation Sites of a Familial Recurrent Patellar Dislocation

Background Recurrent patellar dislocation is the result of anatomical alignment and imbalance of restraint of bone and soft tissue. To investigate the anatomical characteristics of the knee joint in a family of patients with recurrent patella dislocation, and to screen the possible pathogenic genes in this family by whole exon sequencing in 4 patients and 4 healthy subjects, so as to provide theoretical basis for the pathogenesis of this disease. Methods The data related to patella dislocation were measured by imaging data. The peripheral blood DNA of related family members was extracted for full exon sequencing, and then the sequencing results were compared with the human database. By filtering out synonymous mutations and high-frequency mutations, and then integrating single nucleotide non-synonymous mutations of family members, disease-causing genes were found. Results All patients in this family have different degree of abnormal knee anatomy, which is closely related to patella dislocation. The sequencing results of patients and normal persons in this patella dislocation family were compared and analyzed, and the data were filtered through multiple biological databases. Find HOXB9(NM_024017.4:p.Glu135Gly/c.404A>G),COL1A1(NM_000088.3:p.Ala1256 Thr/c.3766G>A),GNPAT(NM_014236.3:p.Asp519Gly/c1556A>G),NANS(NM_018946.3:p.Glu68Asp/c.204G>C),SLC26A2(NM_000112.3:p.Thr689Ser/c.2065A>T) are not synonymous mutations (MISSENSE). Through Sanger sequencing, HOXB9 and SLC26A2 genes were found to be the pathogenic genes of this family with recurrent patella dislocation. Conclusions The anatomical structure of the knee joint of patients with recurrent patellar dislocation in this family is obviously abnormal. HOXB9 mutation may be the high frequency pathogenic gene of recurrent patella dislocation in this family, while COL1A1, GNPAT, NAans, SLC26A2 gene may be the sporadical pathogenic gene.

The Frequency, Penetrance and Variable Expressivity of Dilated Cardiomyopathy-Associated Putative Pathogenic Gene Variants in UK Biobank Participants

Background: There is a paucity of data regarding the phenotype of dilated cardiomyopathy (DCM) gene variants in the general population. We aimed to determine the frequency and penetrance of DCM-associated putative pathogenic gene variants in a general, adult population, with a focus on the expression of clinical and subclinical phenotype, including structural, functional and arrhythmic disease features. Methods: UK Biobank participants who had undergone whole exome sequencing (WES), ECG and cardiovascular magnetic resonance (CMR) imaging were selected for study. Three different variant calling strategies (one primary and two secondary) were used to identify subjects with putative pathogenic variants in 44 DCM genes. The observed phenotype was graded to either 1) DCM (clinical or CMR diagnosis); 2) early DCM features, including arrhythmia and/or conduction disease, isolated ventricular dilation, and hypokinetic non-dilated cardiomyopathy; or 3) phenotype-negative. Results: Among 18,665 individuals included in the study, 1,463 (7.8%) subjects possessed ≥1 putative pathogenic variant in 44 DCM genes by the main variant calling strategy. A clinical diagnosis of DCM was present in 0.34% and early DCM features in 5.7% of individuals with putative pathogenic variants. ECG and CMR analysis revealed evidence of subclinical DCM in an additional 1.6% and early DCM features in 15.9% of individuals with putative pathogenic variants. Arrhythmias and/or conduction disease (15.2%) were the most common early DCM features, followed by hypokinetic non-dilated cardiomyopathy (4%). The combined clinical/subclinical penetrance was ≤30% with all three variant filtering strategies. Clinical DCM was slightly more prevalent among participants with putative pathogenic variants in definitive/strong evidence genes, as compared to those with variants in moderate/limited evidence genes. Conclusions: In the UK Biobank, approximately 1/6 of adults with putative pathogenic variants in DCM genes exhibited a subclinical phenotype based on ECG and/or CMR, most commonly manifesting with arrhythmias in the absence of substantial ventricular dilation/dysfunction.

Case Report: Neuroblastoma Breakpoint Family Genes Associate With 1q21 Copy Number Variation Disorders

Microduplications and reciprocal microdeletions of chromosome 1q21. 1 and/or 1q21.2 have been linked to variable clinical features, but the underlying pathogenic gene(s) remain unclear. Here we report that distinct microduplications were detected on chromosome 1q21.2 (GRCh37/hg19) in a mother (255 kb in size) and her newborn daughter (443 kb in size), while the same paternal locus was wild-type. Although the two microduplications largely overlap in genomic sequence (183 kb overlapping), the mother showed no clinical phenotype while the daughter presented with several features that are commonly observed on 1q21 microduplication or microdeletion patients, including developmental delay, craniofacial dysmorphism, congenital heart disease and sensorineural hearing loss. NBPF15 and NBPF16, two involved genes that are exclusively duplicated in the proband, may be the cause of the clinical manifestations. This study supports an association between NBPF genes and 1q21 copy number variation disorders.

The Importance of Extended Analysis Using Current Molecular Genetic Methods Based on the Example of a Cohort of 228 Patients with Hereditary Breast and Ovarian Cancer Syndrome

In about 20–30% of all women with breast cancer, an increased number of cases of breast cancer can be observed in their family history. However, currently, only 5–10% of all breast cancer cases can be attributed to a pathogenic gene alteration. Molecular genetic diagnostics underwent enormous development within the last 10 years. Next-generation sequencing approaches allow increasingly extensive analyses resulting in the identification of additional candidate genes. In the present work, the germline molecular diagnostic analysis of a cohort of 228 patients with suspected hereditary breast and ovarian cancer syndrome (HBOC) was evaluated. The 27 pathogenic gene variants initially detected are listed, and their distribution in the high-risk BRCA1 and BRCA2 genes is presented in this study. In ten high-risk patients, in whom, to date, no pathogenic variant could be detected, an extended genetic analysis of previously not considered risk genes was performed. Three variants of uncertain significance and one pathogenic variant could be described. This proves the importance of extended analysis using current molecular genetic methods.

Colchicine – an effective treatment for children with a clinical diagnosis of autoinflammatory diseases without pathogenic gene variants

Background Autoinflammatory diseases (AID) are rare chronic conditions with high disease burden, affecting children and adults. Clinically and genetically confirmed, AID can be effectively treated with targeted cytokine inhibition. In contrast, for patients with clinical AID symptoms without pathogenic gene variants, no treatment recommendations are available. Colchicine is approved and established as effective, safe and low-cost first-line therapy in Familial Mediterranean Fever. Up to now, efficacy data for colchicine in children with a clinical AID diagnosis without pathogenic gene variants are rare. This pilot study was performed to evaluate the effectiveness of colchicine in children with a clinical diagnosis of AID without pathogenic gene variants. Methods A pilot cohort study of consecutive children with active clinical AID without pathogenic gene variants treated with colchicine monotherapy was performed between 01/2009 and 12/2018. Demographics, clinical and laboratory characteristics were determined serially. Colchicine dosing and safety were documented. Physician estimate of disease activity was captured on visual analogue scales (VAS). Primary outcome: Complete response (PGA ≤2 plus CRP ≤0.5 mg/dL and/or SAA ≤10 mg/L) at last follow-up. Secondary outcomes: partial/no response, flare characteristics and requirement for rescue therapies. Analysis: Nonparametric comparison of disease activity measures. Results A total of 33 children were included; 39% were female. Median age at colchicine start was 3.8 years, median follow-up was 14.1 months. Clinical AID diagnoses included CAPS (24%), FMF (27%), PFAPA (43%) and unclassified AID (6%). At baseline, overall disease activity was moderate (PGA 4), inflammatory markers were elevated (CRP 12.1 mg/dL; SAA 289.2 mg/L), and 97% reported febrile flares. Outcome: 55% achieved complete response, 35% showed partial response and 58% had no febrile flares at last follow-up. Inflammatory markers (SAA: p < 0.0001, CRP: p < 0.005) and disease activity (p < 0.0001) decreased significantly. Overall, 93% of children experienced improvement of flare characteristics. Conclusion Colchicine was found to be effective and safe in children with a clinical AID diagnosis in the absence of pathogenic gene variants. Colchicine is a low-cost treatment option for non-organ threatening AID.

Precision Therapy for a Chinese Family With Maturity-Onset Diabetes of the Young

ObjectiveTo determine the pathogenic gene and explore the clinical characteristics of maturity-onset diabetes of the young type 2 (MODY2) pedigree caused by a mutation in the glucokinase (GCK) gene.MethodsUsing whole-exome sequencing (WES), the pathogenic gene was detected in the proband—a 20-year-old young man who was accidentally found with hyperglycemia, no ketosis tendency, and a family history of diabetes. The family members of the proband were examined. In addition, relevant clinical data were obtained and genomic DNA from peripheral blood was obtained. Pathologic variants of the candidate were verified by Sanger sequencing technology, and cosegregation tests were conducted among other family members and non-related healthy controls. After adjusting the treatment plan based on the results of genetic testing, changes in biochemical parameters, such as blood glucose levels and HAblc levels were determined.ResultsIn the GCK gene (NM_000162) in exon 9, a heterozygous missense mutation c.1160C &gt; T (p.Ala387Val) was found in the proband, his father, uncle, and grandmother. Thus mutation, which was found to co-segregate with diabetes, was the first discovery of such a mutation in the Asian population. After stopping hypoglycemic drug treatment, good glycemic control was achieved with diet and exercise therapy.ConclusionGCK gene mutation c.1160C &gt; T (p.Ala387Val) is the pathogenic gene in the GCK-MODY pedigree. Formulating an optimized and personalized treatment strategy can reduce unnecessary excessive medical treatment and adverse drug reactions, and maintain a good HbA1c compliance rate