Familial Intracranial Aneurysm: Influence of Genetical Variations of Collagen - Ala459Pro - and its relations to Arterial Hypertension and Diabetes Mellitus

• Grant number: 11/10819-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2011
• End date: September 30, 2012
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Dorotéia Rossi Silva Souza
• Grantee: Luis Felipe Machado Lauletta
• Host Institution: Faculdade de Medicina de São José do Rio Preto (FAMERP). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São José do Rio Preto , SP, Brazil

Abstract

Hemorrhagic Stroke can occur after the rupture of Intracranial Aneurysm (IA) or as result of other vascular malformations. Bleeding could make intracranial pressure higher, leading to tissue damage. Some risk factors for IA are to be highlighted, like old age, feminine gender, smoking and drinking habits, Systemic Arterial Hypertension and genetic factors. Diabetes Mellitus plays a controversial role at the pathology of IA, being, on one hand, characterized by some authors as a risk factor and, on the other hand, as a protective factor against rupture of IA by some others. It is also important to analyze the genes that are related to the formation of arterial walls, like COL1A2, whose polymorphisms could change the wall's integrity. The present study's objectives are to analyze the prevalence of Ala459Pro polymorphism of COL1A2 in patients with familial IA, and their respective first-grade relatives; evaluate the influence of Arterial Hypertension and Diabetes Mellitus at IA manifestation, and its relation to the polymorphism Ala459Pro of Col1A2. 400 individuals will be selected, independently from gender, ethnical group and age. They will be distributed in six groups. Group 1 - 40 individuals diagnosed with familial IA (G1); Group 2 - 160 first-grade relatives of G1 (G2); Group 3 - 100 individuals without disease with negative subtraction digital angiography (G3); Group 4 - 100 first-grade relatives of G3 (G4). COL1A2 variations will be submitted to conventional Polymerase Chain Reaction (PCR), agarose gel and GelRed coloration. The result of this process will suffer the action of restriction enzyme MspA1I (New England), under 37°C for 16 hours. Afterwards, the solution shall be colored by GelRed (Uniscience), separated by electrophoresis in 2% agarose gel, under constant 150 V electric current during 45 minutes. This gel will be visualized by means of photo documentation of the fragments' genotypes, as they have different pairs of base (472, 312, 115).