👤 Rafael Maffei Loureiro

Genetic factors are thought to play an important role in antipsychotic-induced weight gain (AIWG). Polygenic risk scores (PRS) could provide a measure of genetic predisposition to antipsychotic drug induced weight gain (AIWG).We conducted a study to examine how a PRS, generated using SNPs, identified from a recent meta-analysis, related to weight-change over time in people with first episode-psychosis. The PRS included SNPs in six different genes, identified as having significant associations (p < 0.05) with AIWG. These were HTR2C rs3813929; MTHFR rs1801133; ADRA2A rs1800544; MC4R rs489693; LEPR rs1137101 and CNR1 rs1049353. An additive PRS and a risk allele based weighted PRS were created based on risk allele counts and presence or absence of risk alleles respectively. The additive PRS was also used to create low/high genetic risk groups for analysis. The association between PRS and weight gain per day (WGPD) in grams/day as well as BMI percentage change (=> 7%) was investigated using regression models. In multiple regression analysis, the additive PRS significantly predicted AIWG in females (adjusted r We report a PRS that is predictive of weight gain in women treated for first episode psychosis, accounting for 59% of the variance daily weight-gain over time. Validation in an independent cohort is required, as is determining whether it is feasible to apply the PRS prospectively. Show less

Metabolic side effects represent a major long-term concern in antipsychotic (AP)-treated early psychosis. We evaluated the weight gain and changes in related metabolic parameters in patients followed up for 12 months. We also explored DNA methylation of four genes associated with weight gain (ADRA2A, INSIG2, LEP, MC4R). We included patients aged 15-64 years followed in the Ribeirão Preto Early Intervention in Psychosis Program from two different cohorts (Clinical sample, n = 147; Epigenetic sample, n = 59). DNA methylation was analysed by pyrosequencing only at baseline, after several weeks of AP exposure. In both cohorts, 40% of patients initially received second-generation antipsychotics (SGAs), increasing to over 70% after one year. Clinical sample: At follow-up, patients exhibited significant increases in body mass index (p < 0.001), triglycerides (p < 0.001), HDL-c (p = 0.001) and LDL-c (p < 0.001). Patients predominantly on SGAs during the 12 months had almost three times higher chance of weight gain than those using haloperidol. Other factors associated with weight gain included non-white skin colour (OR = 2.6), fewer years of schooling (OR = 2.5) and a weight gain of at least 7% at three months (OR = 3.1). Epigenetic sample: Patients receiving SGA treatment (median = 23.4 weeks) at baseline showed hypermethylation within the MC4R promoter region in relation to patients using haloperidol (median = 18.6 weeks). No changes in the baseline methylation of other genes related to weight gain or AP drugs were observed longitudinally. MC4R promoter hypermethylation in SGA-treated patients suggests drug-induced metabolic alterations and a potential role of MC4R as a biomarker for predicting AP-related metabolic risk. Show less

Genetic factors are thought to play an important role in antipsychotic-induced weight gain (AIWG). This study conducted a meta-analysis of current research of the pharmacogenetic associations of adult AIWG. The analysis included papers providing comparisons of weight gain across at least two allele combinations for at least one single nucleotide polymorphism (SNP). Inclusion criteria were, patients 18 years of age or older and had received a diagnosis of severe mental illness, for which antipsychotic medication was prescribed. The association with AIWG needed to be replicated across at least two papers reporting separate sample sets. Two hundred twenty-three papers were assessed for eligibility. Of the 223 papers, 148 were excluded, leaving 75 studies to be included. Six SNPs in six different genes were identified as having significant associations ( The study identified six SNPs that predispose adult individuals to AIWG, with Show less

Hypertriglyceridemia (HTG) is a common dyslipidemia associated with an increased risk of cardiovascular disease and pancreatitis. It is well stablished that the severe cases of disease often present with an underlying genetic cause. In this study, we determined the frequency and variation spectrum of genes involved in the triglyceride metabolism in a series of Brazilian patients with severe HTG. A total of 212 patients with very high HTG, defined with fasting triglycerides (TG) ≥ 880 mg/ dL, that underwent a multi-gene panel testing were included in this research. Germline deleterious variants (i.e. Pathogenic/Likely Pathogenic (P/LP) variants) were identified in 28 out of 212 patients, reflecting an overall diagnostic yield of 13% in our cohort. Variants of unknown significance (VUS) were identified in 87 patients, and represent 80% of detected variants in this dataset. We confirm the Show less

We aim to characterize patients with Gomez-López-Hernández syndrome (GLHS) clinically and to investigate them molecularly. A clinical protocol, including a morphological and neuropsychological assessment, was applied to 13 patients with GLHS. Single-nucleotide polymorphism (SNP) array and whole-exome sequencing were undertaken; magnetic resonance imaging was performed in 12 patients, including high-resolution, heavily T2-weighted sequences (HRT2) in 6 patients to analyze the trigeminal nerves. All patients presented alopecia; two did not present rhombencephalosynapsis (RES); trigeminal anesthesia was present in 5 of the 11 patients (45.4%); brachycephaly/brachyturricephaly and mid-face retrusion were found in 84.6 and 92.3% of the patients, respectively. One patient had intellectual disability. HRT2 sequences showed trigeminal nerve hypoplasia in four of the six patients; all four had clinical signs of trigeminal anesthesia. No common candidate gene was found to explain GLHS phenotype. RES does not seem to be an obligatory finding in respect of GLHS diagnosis. We propose that a diagnosis of GLHS should be considered in patients with at least two of the following criteria: focal non-scarring alopecia, rhombencephalosynapsis, craniofacial anomalies (brachyturrycephaly, brachycephaly or mid-face retrusion), trigeminal anesthesia or anatomic abnormalities of the trigeminal nerve. Studies focusing on germline whole genome sequencing or DNA and/or RNA sequencing of the alopecia tissue may be the next step for the better understanding of GLHS etiology. Show less