Genetic Mutations Causing PR Clinical Trial
Official title:
Prospective Multicenter Study on the Identification of Genetic Abnormalities Predisposing to Vasospasm From a Privileged Model: the Primary Raynaud's Phenomenon
Vasospasm is a transient contraction causing a decrease in caliber of a vessel and thus a
decrease in vascularization in a vascular territory leading to suffering of tissue in the
sector concerned. Vasospasm-related diseases have different clinical presentations such as
migraine, spastic angina, hypertension related to vasospasm or primary Raynaud's phenomenon
(RP). These diseases have few therapeutic methods due to poorly understood pathophysiology.
For migraine and angina, the vascular exploration is problematic unlike for primary Raynaud's
phenomenon (RP).
Primary Raynaud's phenomenon (RP) is a common peripheral vascular disease to cold with an
estimated prevalence between 5-9 % of the general population. It is the expression of an
extreme vasospasm microcirculation of the extremities linked to hypersensitivity to cold and
that is clinically expressed by the occurrence of syncope stages where the fingers are
anesthetized and white, followed by a stage with hyperemic restaining .
The objective of our study is to identify new metabolic pathways involved in vasospasm in
order to consider new specific treatments, currently lacking.
The identification of these pathways will be made by the detection of genetic abnormalities
causing vasospasm in Raynaud's phenomenon. This disease is a perfectly appropriate model to
study vasospasm by its high frequency in the population, its hereditary nature and simple
diagnosis. The powerful current genetic strategies will be applied to this model (exome
sequencing combined to family connection analysis).
Patients with primary Raynaud phenomenon will be identified during a consultation of vascular
medicine and internal medicine in one of the centers participating to the study. Those
patients with a primary PR will be considered as Index cases.
In all participating centers, there will be a recruitment of index cases without family
screening to form a series of cases that will validate the results obtained in family forms.
The investigators will conduct genealogical trees of index cases to identify families, whose
number of healthy individuals and those with relevant PR makes sense for a family genetic
study, i.e. a genetically informative family.
In all centers, relatives of included Index cases, agreeing to participate in this research,
will be enrolled and followed.
Nantes University Hospital is the only center to perform a cold test (for reasons of
availability of the technique) but this test will be reserved for patients whose diagnosis of
primary Raynaud's phenomenon would be doubtful. Exposed identified relatives, agreeing to
participate in this research, will all be included and followed in their enrollment center.
;