Assoc. Prof. Jesus Lacal

Reproducing RASopathy patient-specific DNA variants for in vitro cellular and molecular analysis

Jesus Lacal, PhD

Functional Genetics of Rare Diseases Laboratory

Biomedicine of Rare Diseases

Division of Genetics - University of Salamanca (USAL)

Institute of Biomedical Research of Salamanca (IBSAL)

Campus Unamuno, Edificio Departamental – 324, 37007, Salamanca (Spain)

Abstract: RASopathies, including Neurofibromatosis type 1 (NF1), Legius syndrome (LS), and Noonan syndrome (NS), are a group of rare genetic diseases caused by germline mutations in the RAS/MAPK signaling pathway. Our laboratory is dedicated to understanding the molecular mechanisms behind these conditions. We work with DNA from pediatric patients identified at the Rare Disease Unit of the University Hospital of Salamanca. Through genetic engineering, we reproduce patient-specific DNA variants in lentiviral vectors, followed by extensive cell and molecular analysis. This study specifically aims to elucidate the molecular mechanisms of LS, focusing on genotype-phenotype correlations and cancer risk. Using in silico analysis of SPRED1 variants from databases we examined the mutational landscape of SPRED1. Eleven variants, including two from our patients, were analyzed in vitro to assess their impact on SPRED1 protein levels and their effect on ERK, AKT, p38, and p53 expression and activation. The study highlights the dysregulation of the RAS/MAPK pathway in LS and suggests potential links to other signaling pathways, offering new insights into the disease's molecular underpinnings.