European Human Genetics Conference 2007 June 16 – 19, 2007 ...

Genetic analysis, linkage, and association
P0961. Mutational screening in Dysferlin gene
L. Gonzalez-Quereda 1 , J. Juan 1 , N. de Luna 2 , E. Gallardo 2 , M. Rodriguez 1 , C.
Paradas 3 , I. Illa 2 , M. Baiget 1 , P. Gallano 1 ;
1 Genetics, Hospital de Sant Pau, Barcelona, Spain, 2 Neurology, Hospital de
Sant Pau, Barcelona, Spain, 3 Neurology, Hospital de Valme, Sevilla, Spain.
Mutations in dysferlin gene (DYSF) cause different muscular dystrophy
phenotypes with autosomal recessive inheritance including Limb
Girdle Muscular Dystrophy 2B (LGMD2B), Miyoshi Myopathy (MM)
and Distal Anterior Compartment Myopathy (DAT). DYSF gene, that
maps to chromosome 2p13, has 55 exons and codifies a protein of
about 237 kDa.
Dysferlin protein is expressed in skeletal muscle and peripheral blood
monocytes. The genomic analysis of the DYSF gene has proved to
be time consuming because its long size. We designed a mutational
screening strategy based on cDNA from monocytes to find out whether
the mutational analysis could be performed in mRNA from a source
less invasive than the muscle biopsy
We studied 50 patients from 31 families clinically diagnosed as MM,
LGMD2B and DAT through: 1) the analysis of dysferlin expression by
immunohystochemistry in muscle biopsies and Western blot in peripheral
blood monocytes and, 2) the screening of mutations in DYSF gene
by sequencing monocytes cDNA, amplifying 14 fragments that covers
the 55 exons. Finally, the results were confirmed in genomic DNA.
We identified mutations in DYSF gene in the thirty one families studied:
17 of them in a homozygous state and 14 in a heterozygous state.
We found the two mutated alleles in twenty eight families and only one
mutated allele in 3 families. Seventeen mutations were missense, 10
nonsense, 13 frameshit and 2 splice site mutations.
This report furnish evidence of reliable mutational analysis using
monocytes cDNA and constitutes a good alternative to genomic DNA
analysis.
P0962. Haplotypic classification of DEB in Tunisia: evidence for
genetic variability among the different geographic regions
H. Ouragini 1 , F. Cherif 2 , W. Daoud 2 , S. Kassar 3 , S. Nouira 1 , S. Boubaker 3 , A.
Ben Osman-Dhahri 2 , S. Abdelhak 1 ;
1 Molecular Investigation of Genetic Orphan Diseases, Institut Pasteur de Tunis,
Tunis, Tunisia, 2 Dermatology department, Hôpital de la Rabta, Tunis, Tunisia,
3 Anatomo-Pathology service, Institut Pasteur de Tunis, Tunis, Tunisia.
The dystrophic epidermolysis bullosa (DEB), a group of heritable blistering
skin diseases, is characterized by abnormalities in the anchoring
fibrils at the dermal-epidermal basement membrane zone. Mutations
within COL7A1 gene that encodes type VII collagen, the major component
of the anchoring fibrils, is responsible for DEB.
In order to study the mutational spectrum of DEB in Tunisia, we classify
the DEB Tunisian patients on the basis of their haplotype. Thirty recessive
DEB patients, belonging to 24 families, have been genotyped
with five microsatellite markers overlapping the COL7A1 region.
The genetic investigation showed that there are two common haplotypes,
3-1-6-3-3 and 1-11-14-6-6, which are shared by 6 and 2 families
respectively. The most frequent haplotype, 3-1-6-3-3, shared by 25%
of the families, is mainly found among families originating from Central
Tunisia, and the second one, 1-11-14-6-6, shared by 8% is found
among families originating from North Eastern region. The other studied
DEB patients have different haplotype and scattered on different
cities of the country. All together, seven different haplotypes have been
identified. This study shows haplotypic heterogeneity among Tunisian
DEB families, thus suggesting a mutational heterogeneity.
P0963. The ACE insertion/deletion genotype is associated with
elite athletic performance
R. E. Amir 1 , M. Sagiv 1 , E. Attias 1 , C. Yamin 1 , M. Sagiv 1 , Y. Meckel 1 , O. Amir 2 ;
1 Zinman College of Physical education and sport sciences at the wingate institute,
Netanya, Israel, 2 Lady Davis Carmel Medical Center, Haifa, Israel.
Background: Growing evidence suggests a significant genetic contribution
to human physical performance. The deletion (D) allele of angiotensin-I
converting (ACE) gene has been associated with higher
ACE activity. In the current study we evaluated the association between
ACE ID polymorphism and elite endurance athletic ability.
Methods: Ninety-two elite athletes, classified as either endurance type
performers (51 long distance runners and triathletes) or power athletes
(41 sprinters and long jumpers), were genotyped for the ACE ID polymorphism
using polymerase chain reaction on leukocytes DNA. Their
ACE genotypes were compared to those of 405 healthy individuals.
Results: Allele and genotype frequencies differed significantly between
the groups. The frequency of the D allele was 0.78 in the elite
long distance runners and triathletes, 0.66 in the control group, and
0.57 in the sprinters and long jumpers (Χ 2 = 10.04, P = 0.006). Moreover,
the ACE DD genotype was significantly more prevalent among
the long distance runners (0.63) compared to the controls (0.43), and
compared to the sprinters and long jumpers (0.34) (Χ 2 = 21.99, P =
0.0002). Importantly, in the group of elite athletes the odds ratio of ACE
DD genotype for endurance performance was 3.24 (95% confidence
interval 1.38-7.61), and of ACE II genotype was 0.25 (95% confidence
interval 0.06-0.97).
Conclusions: The present study clearly indicates a positive association
of the ACE D allele with sustained high-level endurance performance.
These data support the notion that increased ACE activity may be of
benefit to endurance-type elite athletes.
P0964. Association of TNF-alpha G-308A promoter
polymorphism with human embryo viability
M. S. Nazarenko, V. P. Puzyrev, I. N. Lebedev;
State Research Institute of Medical Genetics, Tomsk, Russian Federation.
Tumor necrosis factor alpha (TNF-alpha), a multifunctional cytokine, is
expressed in embryonic tissues practically at all stages of human development.
It is believed that TNF-alpha boosts death signaling to kill
the embryo if damages triggered by detrimental stimuli may culminate
in structural anomalies, and stimulate protective mechanisms if the repair
of these damages may prevent maldevelopment. Nonetheless,
no data about the influence of TNF-alpha G-308A promoter polymorphism
for embryo viability itself are found. Samples of trophoblast tissue
from delayed miscarriages (n=118) and dried blood spots of newborns
(n=300) were analyzed for TNF-alpha G-308A polymorphism.
The genotypes -308GA and -308AA TNF-alpha were more prevalent
among newborns (24%) than in the group of delayed miscarriages
(14.4%; P=0.03). Carriers of allele -308A predominated in the neonatal
group to compare with delayed miscarriages (12,3% vs. 7,2%;
P=0.04). In conclusion, high frequency of mutant TNF-alpha allele
among newborns reflect the possible advantage for embryo survival,
that in turn, may lead to its stable frequency in population.
P0965. Polymorphism of IL4RA gene is associated with
endometriosis
M. A. Kozlovskaya 1,2 , G. S. Demin 1,2 , M. I. Yarmolinskaya 1 , T. E. Ivashchenko 1 ,
V. S. Baranov 1,2 ;
1 Ott’s Institute of Obstetrics & Gynecology, St.-Petersburg, Russian Federation,
2 Saint-Petersburg State University, Saint-Petersburg, Russian Federation.
Endometriosis is a common multifactorial disease. Typical endometrioid
cells are characterized by increased cytokine activity. Cytokine
genes are highly polymorphic that results in synthesis of proteins with
various functional activities. This study is devoted to definition of role
of allelic variants of IL4 and IL4RA genes in pathogenesis of endometriosis.
DNA samples from the patients with endometriosis (n=36) and control
group of women without any gynecologic complications (n=69) were
included in the study. Polymorphisms of IL4 (-590T>C) and IL4RA
(1902A>G or Gln551Arg) were defined by PCR-RFLP assay.
The distribution of IL4 and IL4RA genotypes was in agreement with
the HWE law (p>0.05). The frequencies of alleles and genotypes of
IL4 gene did not differ between studied groups (p>0.05). However the
frequency of Arg/Arg genotype of IL4RA gene was significantly higher
in patients with endometriosis (16.7%) than in control group (1.4%,
p