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Context: Severe forms of growth hormone insensitivity (GHI) are characterized by extreme short stature, dysmorphism, and metabolic anomalies. Objective: This work aims to identify the genetic cause of growth failure in 3 "classical" GHI individuals. Methods: A novel intronic growth hormone receptor gene (GHR) variant was identified, and in vitro splicing assays confirmed aberrant splicing. A 6O pseudoexon GHR vector and patient fibroblast analysis assessed the consequences of the novel pseudoexon inclusion and the impact on GHR function. Results: We identified a novel homozygous intronic GHR variant (g.5:42700940T > G, c.618+836T > G), 44 bp downstream of the previously recognized intronic 6 GHR pseudoexon mutation in the index patient. Two siblings also harbored the novel intronic 6O pseudoexon GHR variant in compound heterozygosity with the known GHR c.181C > T (R43X) mutation. In vitro splicing analysis confirmed inclusion of a 151-bp mutant 6O pseudoexon not identified in wild-type constructs. Inclusion of the 6O pseudoexon causes a frameshift resulting in a nonfunctional truncated GHR lacking the transmembrane and intracellular domains. The truncated 6O pseudoexon protein demonstrated extracellular accumulation and diminished activation of STAT5B signaling following GH stimulation. Conclusion: Novel GHR 6O pseudoexon inclusion results in loss of GHR function consistent with a severe GHI phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure. The 2 kindreds originate from the same town in Campania, Southern Italy, implying common ancestry. Our findings highlight the importance of studying variation in deep intronic regions as a cause of monogenic disorders. [ABSTRACT FROM AUTHOR]

Objectives: Recent evidence linked early menarche to a higher risk of insulin-resistance (IR) and nonalcoholic fatty liver disease (NAFLD) in adulthood. We aimed to evaluate the impact of early menarche on glucose derangements and NAFLD in a sample of Italian adolescents with obesity., Methods: Anthropometric and biochemical evaluations were conducted in all the enrolled 318 obese patients (mean age 12.31 ± 2.95 years). NAFLD was defined by the presence of ultrasound detected liver steatosis and/or alanine transaminase (ALT) levels >40 IU/L., Results: Patients with early menarche showed both higher homeostasis model assessment of insulin-resistance (HOMA-IR) (p=0.008) and ALT (p=0.02) values, an increased prevalence of NAFLD (p=0.001), and lower Matsuda and Insulinogenic Index (IGI) values than the other obese patients. The association between early menarche and both ALT and Matsuda Index remained significant in General Linear Models (GLMs) in which respectively body mass index standard deviation score (BMI-SDS) and Matsuda Index, and BMI-SDS were included as covariates. Patients with early menarche also showed a higher risk of both HOMA-IR>3 (OR 1.69, CI 1.05-2.70, p=0.02) and NAFLD (OR 1.10, CI 1.01-1.21, p=0.03)., Conclusions: Girls with obesity presenting early menarche showed higher HOMA-IR levels, lower Matsuda Index and IGI values, and higher risk of NAFLD compared to girls without early menarche., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

Background: Prokineticin receptor 2 (PROKR2) loss of function mutations have been described as cause of hypogonadotropic hypogonadism. In 2017, a first case of central precocious puberty (CPP) caused by PROKR2 heterozygous gain of function mutation was described in a 3.5 years-old girl. No other cases have been reported yet. This study performs a molecular screening in girls with early onset CPP (breast budding before 6 years of age) to identify possible alterations in PROKR2., Methods: We analysed DNA of 31 girls with idiopathic CPP diagnosed via basal LH levels > 0.3 IU/L or peak-LH > 5 IU/L after stimulation, without any MKRN3 mutations. The Fisher exact test was used to compare polymorphism allele frequency to corresponding ones in genome aggregation database (gnomAD)., Results: No rare variants were identified. Five polymorphisms were found (rs6076809, rs8116897, rS3746684, rs3746682, rs3746683). All except one (i.e. rs3746682) had a minor allele frequency (MAF) similar to that reported in literature. rs3746682 presented a MAF higher than that described in the gnomAD (0.84 in our cohort vs 0.25 from gnomAD)., Conclusions: As for other G protein-coupled receptors (i.e. GPR54), mutations in PROKR2 do not seem to be a frequent cause of CPP in girls.

PNPLA3 and MTP genes have been associated with liver steatosis and chronic hepatitis C. We studied the influence of MTP and PNPLA3 polymorphisms in 114 Italian patients with chronic hepatitis C, evaluating the histological and clinical presentation of liver disease. The study confirmed the association of PNPLA3 polymorphisms with liver steatosis (p=0.041), but did not show any additive effect of MTP polymorphisms in the development of steatosis. MTP polymorphisms do not seem to influence PNPLA3 in the development of liver steatosis. Further studies with a larger number of patients are required.

Background: The patatin-like phospholipase domain-containing 3 gene (PNPLA3) has been associated with liver steatosis and disease progression in nonalcoholic steatohepatitis and chronic hepatitis C., Aims: The aim of the present study was to evaluate the influence of the PNPLA3 I148M polymorphisms on the clinical, histological, viral, and host parameters in Italian patients with chronic hepatitis B (CHB)., Methods: Ninety-nine patients with CHB entered the study and underwent a clinical, histological, virological, and biochemical evaluation. PNPLA3 (p.I148M) variants were genotyped., Results: PNPLA3 rare variant (148M) was significantly associated with liver steatosis (p = 0.0019) and cholesterol (p = 0.04) levels, but not with fibrosis or histological activity index. The 13 patients with severe liver steatosis (score > 3) (38%) were more frequently homozygous for PNPLA3 148M variant than the 86 without (6%, p = 0.003). At logistic regression analysis, severe steatosis was independently associated with the rare allele (p = 0.001) and waist circumference, but not with body mass index (BMI)., Conclusions: In our CHB patients, the PNPLA3 polymorphisms influenced the development of liver steatosis, but not fibrosis status. The association of PNPLA3 p.I148M with liver steatosis increased with the greater amount of abdominal fat, irrespective of BMI.

Background & Aims: A common non-synonymous polymorphism, E167K, in transmembrane six superfamily member 2 (TM6SF2) gene has been recently associated with an increased hepatic triglyceride content, dyslipidemia and liver fibrosis in NAFLD patients. We investigated possible associations between the TM6SF2 variants and liver lesions in chronic hepatitis C., Patients and Methods: 148 consecutive patients with biopsy proven anti-HCV/HCV-RNA-positive chronic hepatitis, naive for antiviral therapy, were genotyped for TM6SF2 E167K and PNPLA3 I148M variants., Results: The score of liver steatosis was higher in the 18 patients with TM6SF2 E167K variant (mean 1.9 ± 1.3) than in the 130 homozygotes for TM6SF2 167E allele (1.1 ± 1.1, P = 0.02), and the prevalence of a steatosis score ≥ 3 was 33.3% vs. 12.3% respectively (P = 0.02). No difference in necroinflammatory or fibrosis scores was found between the two groups. A general linear model identified as independent predictors of steatosis TM6SF2 E167K and PNPLA3 M148M variants and waist circumference (P = 0.0376, P = 0.0069 and P = 0.0273 respectively)., Conclusions: This is the first demonstration that TM6SF2 E167K variant is an independent predictor of liver steatosis in chronic hepatitis C., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Context: Obesity and iron deficiency are two of the most common nutritional disorders worldwide. Several studies found higher rates of iron deficiency in obese than in normal-weight children. Hepcidin represents the main inhibitor of intestinal iron absorption, and its expression is increased in adipose tissue of obese patients. Leptin is able, in vitro, to raise hepcidin expression., Objectives: Aims of this work were 1) to assess the association between poor iron status and obesity, 2) to investigate whether iron homeostasis of obese children may be modulated by serum hepcidin variations, and 3) to assess the potential correlation between leptin and serum hepcidin variations., Methods: Iron status and absorption as well as hepcidin, leptin, and IL-6 levels were studied in 60 obese children and in 50 controls., Results: Obese children showed lower iron and transferrin saturation (both P < 0.05) and higher hepcidin levels (P = 0.004) compared with controls. A direct correlation between hepcidin and obesity degree (P = 0.0015), and inverse correlations between hepcidin and iron (P = 0.04), hepcidin and transferrin saturation (P = 0.005), and hepcidin and iron absorption (P = 0.003) were observed. A correlation between leptin and hepcidin (P = 0.006) has been found. The correlation remained significant when adjusted for body mass index, sex, pubertal stage, and IL-6 values., Conclusions: We propose that in obese patients, increased hepcidin production, at least partly leptin mediated, represents the missing link between obesity and disrupted iron metabolism.

Background: Melanocortin-4-receptor (MC4R) mutations represent the most frequent genetic cause of non-syndromic early onset obesity. Children carrying MC4R mutations seem to show a particular phenotype characterized by early onset, severe obesity and high stature. To verify whether MC4R mutations are associated with this particular phenotype in the Italian pediatric population, we decided to screen the MC4R gene in a group of obese children selected on the basis of their phenotype., Methods: To perform this study, a multicentric approach was designed. Particularly, to be enrolled in the study subjects needed to meet the following criteria: Body mass index > or = 3 deviation scores according to age and sex, familiar history of obesity (at least one parent obese), obesity onset before the 10 years old, height > or = 2 deviation scores. The coding region of MC4R gene was screened in 240 obese children (mean age 8.3 +/- 3.1, mean BMI 30.8 +/- 5.4) and in 200 controls (mean age 8.1 +/- 2.8; mean BMI 14.2 +/- 2.5)., Results: Three mutations have been found in five obese children. The S127L (C380T), found in three unrelated children, had been described and functionally characterized previously. The Q307X (C919T) and the Y332H (T994C) mutations were found in two patients. Functional studies showed that only Q307X impaired protein function., Conclusion: The low prevalence of MC4R mutations (1.6%) in this group of obese children selected according to the obesity degree, the tall stature and the family history of obesity was similar to the prevalence observed in previous screenings performed in obese adults and in not phenotypically selected obese children.