2008 Barcelona - European Society of Human Genetics

Molecular and biochemical basis of disease
P06.290
DNA diagnostics in tuberous sclerosis - development of reliable
and economical test
R. Vrtel 1 , H. Filipová 1 , R. Vodicka 1 , G. Voutsinas 2 , D. Konvalinka 3 , A. Santava 1 ,
J. Santavy 1 ;
1 University Hospital and Palacky University Olomouc, Olomouc, Czech Republic,
2 NCSR ‘’DEMOKRITOS’’, Institut of Biology, Athens, Greece, 3 CGB laboratory,
Ostrava, Czech Republic.
Tuberous sclerosis (TSC) is inherited autosomal dominant disorder
with incidence of up to 1/5 .800 births . Almost 80% of cases are new
mutations . Extreme clinical variability complicates diagnostics and
genetic counselling . Accurate diagnosis is essential in order to detect
and treat a life threatening neurological, renal and cardiac lesions and
for prenatal diagnosis purposes . Mutations in TSC1 and TSC2 tumorsuppressor
genes were shown to be responsible for development of
TSC . The TSC2 gene on 16p13 .3 spans over 41 exons, coding for
tuberin and the TSC1 gene on 9q34 has 21 exons coding for hamartin
. No ,,hot-spot“ with more frequent mutation occurrence was found .
Presented study is a project of bilateral Czech-Greek cooperation in
research and development, ME 923 . The aim is to establish a comprehensive
genetic test for the analysis of TSC mutations in Greek and
Czech patients . Greek team is introducing direct sequencing of TSC1
and TSC2 coding sequences what is recent trend, though quite expensive
. Czech team is performing preliminary screening for mutations by
DGGE and LOH test and MLPA for larger rearrangements . Especially
the utilization of LOH test simplifies and accelerates TSC diagnostics
in some cases. Czech and Greek sample files are exchanged and examined
in the other laboratory . The reliability of DGGE was tested on
positive samples from partners’ lab . Sensitivity of DGGE was proved
on artificial mosaics, revealing 10% mutant lineages. The knowledge
acquired from the research collaboration should contribute significantly
to the development of valid diagnostic methods at a minimum cost .
P06.291
Polymorphism of TNFA gene promoter region and chronic
inflammatory disorders
T. Ivashchenko, J. Nasyhova, J. Ostankova, N. Semenov, V. Baranov;
Ott’s institute of Obstetrics and Gynecology, St.Petersburg, Russian Federation.
Tumor necrosis factor alpha (TNFA) is a potent immunomodulator and
proinflammatory cytokine that has been implicated in the pathogenesis
of chronic inflammatory disorders. Several polymorphisms located in
the promoter region of the TNFA gene have recently been reported to
be associated with production of TNFA . We have studied the genetic
polymorphisms -238G/A and -308G/A of the TNFA gene by PCR-RFLP
analysis in 100 patients with Crohn’s disease, in 71 ulcerative colitis
patients, in 103 asthmatic patients and in relevant population group
(n=117) . It is known that these diseases are characterized by the development
of chronic inflammation.
The analysis of genotypes and alleles distribution for polymorphisms -
238G/A in patient groups and in population has not revealed significant
differences .
For Crohn’s disease the -308A allele of the TNFA gene was detected
in 27% of patients but only in 6 .8% of population (p