Analysis of ACE2 and TMPRSS2 coding variants as a risk factor for SARS-CoV-2 from 946 whole-exome sequencing data in the Turkish population.

Heterogeneity in symptoms associated with COVID-19 in infected patients remains unclear. ACE2 and TMPRSS2 gene variants are considered possible risk factors for COVID-19. In this study, a retrospective comparative genome analysis of the ACE2 and TMPRSS2 variants from 946 whole-exome sequencing data was conducted. Allele frequencies of all variants were calculated and filtered to remove variants with allele frequencies lower than 0.003 and to prioritize functional coding variants. The majority of detected variants were intronic, only two ACE2 and three TMPRSS2 nonsynonymous variants were detected in the analyzed cohort. The main ACE2 variants that putatively have a protective or susceptibility effect on SARS-CoV-2 have not yet been determined in the Turkish population. The Turkish genetic makeup likely lacks any ACE2 variant that increases susceptibility to SARS-CoV-2 infection. TMPRSS2 rs75603675 and rs12329760 variants that were previously defined as common variants that have different allele frequencies among populations and may have a role in SARS-CoV-2 attachment to host cells were determined in the population. Overall, these data will contribute to the formation of a national variation database and may also contribute to further studies of ACE2 and TMPRSS2 in the Turkish population and differences in SARS-CoV-2 infection among other populations.

Comparison of the effect of bipolar coagulation and fibrillar structured oxidized cellulose on formation epidural fibrosis in rats

Background/aim: Epidural fibrosis (EF) is a common cause of failed back surgery syndrome seen after spinal surgeries. The most frequent reason for the formation of EF is accumulated blood and its products in the operation zone. On the development of EF, the effect of bipolar coagulation and fibrillar oxidized cellulose, which are used frequently to control bleeding, was investigated. Materials and methods: In the study, 45 male Sprague Dawley rats were divided into three groups (control, fibrillar, and bipolar). Lumbar laminectomy was applied to all rats under sterile conditions. In the control group, the epidural area was washed with saline solution. Bleeding was controlled with fibrillar oxidized cellulose in the fibrillar group, with bipolar coagulation in the bipolar group. The area to which laminectomy had been applied was removed as a block 6 weeks later and evaluated histopathologically and genetically in terms of EF development. Fibrosis degree was determined histopathologically by counting fibroblasts using the modified Lubina and EF He grading systems. Interleukin-6 (IL-6), transforming growth factor beta-1 (TGFß-1), and mRNA levels were measured by the droplet digital polymerase chain reaction method. Results: The number of epidural fibroblasts, percentage of modified Lubina, amount of IL-6, and He grading rates were significantly lower in the fibrillar group than in the bipolar and control groups (p ˂ 0.05). On the other hand, there was no significant difference among the control, fibrillar, and bipolar groups in terms of TGFß-1 values (p= 0.525). Conclusion: The use of fibrillar oxidized cellulose was more effective for hemostasis than bipolar coagulation in reducing the development of EF.

A case report of Tangier disease presents with acute sensorimotor polyneuropathy and its treatment approach.

Polyneuropathy is a frequently encountered clinical presentation where peripheral nerves are affected due to the same cause and physiopathological processes. We report a case of acute sensorimotor polyneuropathy in a patient with Tangier disease (TD) who was treated with miglustat which is a glycosphingolipid synthesis inhibitor. TD is a very rare genetic disorder caused by mutations in the ATP-binding cassette transporter A1 (ABCA1) gene which encodes the cholesterol efflux regulatory protein. It leads to accumulation of cholesterol esters within various tissues and affects lipid metabolism by deficiency of high-density lipoprotein (HDL) in the blood. Due to the accumulation of cholesterol esters in Schwann cells, it could provoke polyneuropathy in TD. Our case presented to our clinic with quadriparesis and after treated with miglustat therapy his weakness regressed.

Clinical and genetic spectrum from a prototype of ciliopathy: Joubert syndrome.

OBJECTIVE: Joubert syndrome is a neurodevelopmental disorder with a distinctive hindbrain malformation called molar tooth sign, causing motor and cognitive impairments. More than 40 genes have been associated with Joubert syndrome. We aim to describe a group of Joubert syndrome patients clinically and genetically emphasizing organ involvement. METHODS: We retrospectively collected clinical information and molecular diagnosis data of 22 patients with Joubert syndrome from multiple facilities. Clinical exome or whole-exome sequencing were performed to identify causal variations in genes. RESULTS: The most common variants were in the CPLANE1, CEP290, and TMEM67 genes, and other causative genes were AHI1, ARMC9, CEP41, CSPP1, HYLS1, KATNIP, KIAA0586, KIF7, RPGRIP1L, including some previously unreported variants in these genes. Multi-systemic organ involvement was observed in nine (40%) patients, with the eye being the most common, including Leber's congenital amaurosis, ptosis, and optic nerve coloboma. Portal hypertension and esophageal varices as liver and polycystic kidney disease and nephronophthisis as kidney involvement was encountered in our patients. The HYLS1 gene, which commonly causes hydrolethalus syndrome 1, was also associated with Joubert syndrome in one of our patients. A mild phenotype with hypophyseal hormone deficiencies without the classical molar tooth sign was observed with compound heterozygous and likely pathogenic variants not reported before in the KATNIP gene. CONCLUSION: Some rare variants that display prominent genetic heterogeneity with variable severity are first reported in our patients. In our study of 22 Joubert syndrome patients, CPLANE1 is the most affected gene, and Joubert syndrome as a ciliopathy is possible without a classical molar tooth sign, like in the KATNIP gene-affected patients.

Could "Islets of Sparing" Be a Clue for Neutral Lipid Storage Disease with Ichthyosis in Patients with Congenital Ichthyosiform Erythroderma?

The prevalent form of ichthyosis in neutral lipid storage disease (NLSDI) is nonbullous congenital ichthyosiform erythroderma (CIE) characterized by fine, whitish scales on erythematous skin over the whole body. Here, we report a late-diagnosed, 25-year-old woman with NLSDI presenting with diffuse erythema and fine whitish scales throughout the body with patches of apparently normal skin, "islets of sparing" on her lower extremities. We observed that the size of the normal skin islets changed with time, and even the entire lower extremity was covered with erythema and desquamation like the rest of the body. Frozen section histopathological examinations were made from lesional skin and normal-looking skin; no difference was observed in terms of lipid accumulation. The only noticeable difference was the thickness of the keratin layer. In CIE patients, observation of patches of apparently normal skin or "islets of sparing" might be a clue for NLSDI to be distinguished from other CIE conditions.

Evaluation of Glycogen Storage Patients: Report of Twelve Novel Variants and New Clinical Findings in a Turkish Population.

Glycogen storage diseases (GSDs) are clinically and genetically heterogeneous disorders that disturb glycogen synthesis or utilization. Although it is one of the oldest inherited metabolic disorders, new genetic methods and long-time patient follow-ups provide us with unique insight into the genotype-phenotype correlations. The aim of this study was to share the phenotypic features and molecular diagnostic results that include new pathogenic variants in our GSD cases. Twenty-six GSD patients were evaluated retrospectively. Demographic data, initial laboratory and imaging features, and current findings of the patients were recorded. Molecular analysis results were classified as novel or previously defined variants. Novel variants were analyzed with pathogenicity prediction tools according to American College of Medical Genetics and Genomics (ACGM) criteria. Twelve novel and rare variants in six different genes were associated with the disease. Hearing impairment in two patients with GSD I, early peripheral neuropathy after liver transplantation in one patient with GSD IV, epilepsy and neuromotor retardation in three patients with GSD IXA were determined. We characterized a heterogeneous group of all diagnosed GSDs over a 5-year period in our institution, and identified novel variants and new clinical findings. It is still difficult to establish a genotype-phenotype correlation in GSDs.