Search for genetic variants in the p66Shc longevity gene by PCR-single strand conformational polymorphism in patients with early-onset cardiovascular disease.
BACKGROUND
Among the possible candidate genes for atherosclerosis experimental data point towards the longevity gene p66Shc. The p66Shc gene determines an increase of intracellular reactive oxygen species (ROS), affecting the rate of oxidative damage to nucleic acids. Knock-out p66Shc-/- mice show reduction of systemic oxidative stress, as well as of plasma LDL oxidation, and reduced atherogenic lesions. Thus, p66Shc may play a pivotal role in controlling oxidative stress and vascular dysfunction in vivo.


METHODS
We searched for sequence variations in the p66Shc specific region of the Shc gene and its upstream promoter by PCR-SSCP in a selected group of early onset coronary artery disease (CAD) subjects (n. 78, mean age 48.5 +/- 6 years) and in 93 long-living control subjects (mean age 89 +/- 6 years).


RESULTS
The analysis revealed two variant bands. Sequencing of these variants showed two SNPs: -354T>C in the regulatory region of p66Shc locus and 92C>T in the p66 specific region (CH2). Both these variants have never been described before. The first substitution partially modifies the binding consensus sequence of the Sp1 transcription factor, and was detected only in two heterozygous carriers (1 CAD subjects and 1 control subject). The 92C>T substitution in the CH2 region consists in an amino acid substitution at codon 31 (proline to leucine, P31L), and was detected in heterozygous status only in one CAD subject. No subjects homozygous for the two newly described SNPs were found.


CONCLUSIONS
Only two sequence variations in the p66Shc gene were observed in a total of 171 subjects, and only in heterozygotes. Our observations, in accordance to other studies, suggest that important variations in the p66Shc gene may be extremely rare and probably this gene is not involved in the genetic susceptibility to CAD.
Sentinelli
Federica
F
Department of Medical Sciences, Endocrinology, University of Cagliari, Cagliari, Italy. fedesentinelli@yahoo.it
Romeo
Stefano
S
Barbetti
Fabrizio
F
Berni
Andrea
A
Filippi
Emanuela
E
Fanelli
Marzia
M
Fallarino
Mara
M
Baroni
Marco G
MG
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics*; D017668:Age of Onset; D000369:Aged, 80 and over; D003324:Coronary Artery Disease / Q000453:epidemiology / Q000235:genetics*; D004252:DNA Mutational Analysis; D020022:Genetic Predisposition to Disease; D006801:Humans; D008136:Longevity / Q000235:genetics; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D018807:Polymorphism, Single-Stranded Conformational; D011401:Promoter Regions, Genetic; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1
D048868:Adaptor Proteins, Signal Transducing; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1