ACTA ENDOCRINOLOGICA (BUC)

Human populations are faced to the COVID-19 pandemic due to the emerging SARS-CoV-2 coronavirus originating from Wuhan (China) and with dramatic Public Health consequences. Despite periods of panic, the scientific community demonstrated an incredible innovation potential and energy ending up in one year with new vaccines to be used in population. Researchers are interrogating on how individual genetic differences contribute to the diversity of clinical manifestations or ethnic and geographic disparities of COVID-19. While efforts were spent to understand mechanistically the infectious potential of the virus, recent progresses in molecular genetics and bioinformatics allowed the characterization of viral sequence and construction of phylogeographical maps of viral dispersion worldwide. These data will help understanding epidemiological disparities among continents and ethnic populations. Much effort was also spent in analyzing host genetics by studying individual genes involved in innate and immune responses or explaining pathogenesis of comorbidities that complicate the fate of elderly patients. Several international consortia launched already Genome wide Association Studies (GWAS) and whole genome sequencing strategies to identify genetic markers with immediate application in patients at risk of respiratory failure. These new genetic data are important not only for understanding susceptibility factors for COVID-19 but they also contain an important message of hope for mankind warranting our survival and health.

Osteoporosis (OP) is a disease predisposing postmenopausal women to fractures, and often accompanied by insulin resistance (IR) and metabolic syndrome (MetS). Previous studies provided contradictory results concerning prevalence of MetS in postmenopausal OP. To better understand the pathogenesis of IR, we reviewed cellular and molecular aspects and systematically reviewed studies providing homeostasis model assessment (HOMA) index. Bone is an active endocrine organ maintaining its integrity by orchestrated balance between bone formation and resorption. Both osteoblasts and osteoclasts contain receptors for insulin and insulin-like growth factor-1 (IGF-1) operating in skeletal development and in the adult life. Defects in this system generate systemic IR and bone-specific IR, which in turn regulates glucose homeostasis and energy metabolism through osteocalcin. Examination of genetic syndromes of extreme IR revealed intriguing features namely high bone mineral density (BMD) or accelerated growth. Studies of moderate forms of IR in postmenopausal women reveal positive correlations between HOMA index and BMD while correlations with osteocalcin were rather negative. The relation with obesity remains complex involving regulatory factors such as leptin and adiponectin to which the contribution of potential genetic factors and in particular, the correlation with the degree of obesity or body composition should be added.

Genome Wide Association Studies (GWAS) are excellent opportunities to define culprit genes in complex disorders such as the polycystic ovary syndrome (PCOS). PCOS is a prevalent disorder characterized by anovulation, hyperandrogenism and polycystic ovaries, which benefitted from several GWASs in Asians and Europeans revealing more than 20 potential culprit genes near associated single nucleotide variations (SNV). Translation of these findings into the clinical practice raises difficulties since positive hits are surrogate SNVs linked with causative mutations by linkage disequilibrium (LD). Studies in Mediterranean populations (e.g. Southern Europe and North Africa) raise supplementary problems because of a different LD-pattern, which may disrupt the link with causative mutations. Our experience in MEDIGENE program between Tunisia and France enforces the necessity of genetic anthropology studies before translating GWAS data. Tunisians are a heterogeneous population with ancestral Berbers, European, Arab and Sub-Saharan African components while South Europeans display a high level of genetic diversity, partially explained by gene flow from North Africa. Human diversity studies require sampling from Middle East and North Africa (MENA) region that will help to understand genetic factors in complex diseases.

Autoimmune diseases are a heterogeneous group that involves almost any tissue and organ, a patient could frequently present more than one autoimmune disease. Type 1 diabetes mellitus is frequently associated with other autoimmune diseases in polyglandular autoimmune syndrome. Aim of the study is to evaluate a phenotype of diabetic patients with autoimmune diseases. There is a retrospective study; we analyzed type 1 diabetes inpatients from our department in late 4 years based on clinical records. We state that type 1 diabetes mellitus diagnosis is established based on insulin treatment at onset or less than 1 year from onset. We analyzed the presence of the following autoimmune diseases: Graves’ disease, Hashimoto thyroiditis, autoimmune hypothyroidism, Addison’s disease, vitiligo, psoriasis, systemic lupus erythematosus, pernicious anemia. We recorded 151 patients with type 1 diabetes mellitus: 91 (60.3%) women. Mean age was 38.4?15.8 years, mean span of type 1 DM was 12 years, mean age at the onset of DM was 26.5 years, and mean BMI was 23.4 kg /m2. Patients were insulin treated with 2 doses of insulin 11.3%, 3 doses of insulin 41.6%, 4 doses of insulin 45%, and insulin pump 2%. 41 patients (27.2%) associated other autoimmune diseases, most frequently being chronic thyroiditis. Type 1 DM preceded autoimmune disease in 60%. Patients that associated autoimmune disease have mean age at the onset of type 1 DM 29.1 years. Mean glycated hemoglobin among patients with autoimmune diseases was 10.1% vs. 9.9% among patients without autoimmune diseases (NS); mean insulin needs were respectively 0.78 u/kgc vs. 0.72 u/kgc (NS). In conclusion, type 1 DM is frequently associated with other autoimmune diseases, patients being mainly women. The most frequent association is Graves’ disease. In over 50% of cases type 1 DM precedes autoimmune disease with several years. Even though more than half of patients were treated with multiple doses of insulin, glycated hemoglobin was high, slightly higher among patients with autoimmune diseases but the differences were not statistically significant.

Context. Genetic factors are responsible for up to 80% of height variation in humans. SHOX gene mutation could be an important etiologic factor in short stature, being observed in up to 15% of patients. Aim. Our aim was to evaluate the genetic causes of short stature, using classical and molecular cytogenetic techniques by analyzing a group of Romanian patients diagnosed with short stature. Material and methods. Seventy nine patients were analyzed and the main criteria for inclusion in the study was the presence of a height below -2DS. For each of these patients a karyotype was performed. In those with normal karyotype it was indicated FISH technique using probes for SHOX and centromeric regions. Results and discussion. The karyotype revealed the presence of abnormalities in 13 patients (16%), 62% (8 patients) of these being represented by heterosomal abnormalities. SHOX deletion was seen in one patient (2.3%) with short stature and normal karyotype. The initial analysis of the cases with short stature directly by FISH technique can be proposed, using probes for X chromosome centromere and SHOX gene, because it allows, approximately at the same costs with the karyotype, but faster and at a higher rate of mosaicism detection, the explanation of short stature by sex chromosomes abnormalities.

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