Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis

Center for Investigation and Rehabilitation of Hereditary Ataxias (CIRAH), Holguín Province, Cuba.
Clinical Genetics (Impact Factor: 3.93). 08/2010; 78(2):169-74. DOI: 10.1111/j.1399-0004.2009.01358.x
Source: PubMed


Almaguer-Mederosa LE, Falcón NS, Almira YR, Zaldivar YG, Almarales DC, Góngora EM, Herrera MP, Batallán KE, Armiñán RR, Manresa MV, Cruz GS, Laffita-Mesa J, Cyuz TM, Chang V, Auburger G, Gispert S, Pérez LV. Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis.
Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32–79 units. Using a Kaplan–Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34–45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive-testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.

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    • "Ensembl database (Ensembl release 79 -March 2015) show that this gene has 2221 different validated variants, among all of these variants there is the rs1530440 , which was confirmed by several studies to be associated with hypertension or blood pressure , furthermore it was replicated in several different population (Newton-Cheh et al.,2009; Jennifer et al.,2011; Yang et al.2012) The human ATXN2 gene encode for the ataxin-2 protein which is well known to be the molecular bases of spinocerebellar ataxia-2 (SCA2) disease , (Almaguer-Mederosa et al., 2010). The complete image of Ataxin-2 protein role in the cell still under investigation and several models are proposed to explain the main role of this protein , in general, it is accepted to has a certain role/s in RNA regulation . "
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