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

Molecular and biochemical basis of disease
logical and immunological criteria.
Immunopathological process induces both local and general changes
and can negatively influence child development.
Main aim of this project, supported by IGA MZ CR: NR8383-3/2005
is to test if the bronchial hyperreactivity level is associated with certain
alleles or haplotypes of genes (ADAM 33 and STAT 6) involved in
immune system activity in course of allergic illness development and
bronchial epithelium remodelling .
Examination of responsible polymorphisms of ADAM 33 and STAT 6
genes was accomplished by sequence analysis in 20 children with
asthma bronchiale, their sibs and parents and 20 control healthy children.
Statistical evaluation of association of genes polymorphisms with
asthma bronchiale occurrence and bronchial hyperreactivity level in
children will be presented by our poster.
Examination of polymorphisms positively associated with allergic reaction
could become a routine part of diagnostics. The description of
influence of particular sequence changes could contribute to additional
insight to the bronchial hyperreactivity genetic background.
P0675. Functional consequences of eIF2B mutations in cells
from affected patients
L. Horzinski 1 , C. Gonthier 1 , L. Kantor 2 , O. Elroy-Stein 3 , O. Boespflug-Tanguy 1,4 ,
A. Fogli 1 ;
1 INSERM UMR384, Clermont-Ferrand, France, 2 Department of cell reserach
and immunology, George S Wise Faculty of Life Sciences, Tel-Aviv, Israel,
3 Department of cell research and immunology, George S Wise Faculty of Life
Sciences, Tel-Aviv, Israel, 4 CHU, Centre de référence Leucodystrophies, Clermont-Ferrand,
France.
The Childhood Ataxia with diffuse Central nervous system Hypomyelination
(CACH)/Vanishing White Matter (VWM) syndrome is an autosomal
recessive leukodystrophy characterized by a progressive spastic
ataxia and a CSF-like aspect of the white matter on MRI. Severity
is correlated with age at disease onset and with episodes of rapid
deterioration following febrile infection or head trauma. Mutations in
the five subunits of the eIF2B translation initiation factor (alpha to epsilon)
are the most frequent cause of the disease. eIF2B is involved in
the first step of protein synthesis by activating the translation initiation
factor eIF2 thanks to its guanine nucleotide exchange activity (GEF
activity). By regeneration of active eIF2, eIF2B is a key factor in the
cellular stress response. We demonstrated that GEF activity of eIF2B
is decreased 63 CACH/VWM patients lymphoblastoid cell lines (llb)
in correlation with disease severity whereas no significant decrease
was observed in 10 primary fibroblasts. Determination of llb GEF activity
is relevant to prescreen patients eligible for eIF2B sequencing. In
contrast, no difference in reticulum endoplasmic stress responsse was
observed between eIF2B-mutated and control llb whereas mutated fibroblasts
expressed an enhanced response to stress in comparison to
control ones. Therefore we initiated a differential transcriptomic study
(on pangenomic chips arrays) on 10 couples (mutated patients versus
controls) with or without cellular ER-stress. The first results suggest
the involvement of multiple pathways.
P0676. Primary calpainopathy, the new mutation detected in the
CAPN3 gene (the case of Moldavian LGMD2A patient).
V. C. Sacara 1 , E. V. Ilina 2 ;
1 Centre of reproductive health and medical genetics, Chisinau, Republic of
Moldova, 2 Research Centre of Medical Genetics, Moscow, Russian Federation.
Introduction. Limb-girdle muscular dystrophy type 2A (LGMD2A) is an
autosomal recessive muscular disorder caused by mutations in the
gene coding for calpain 3, a calcium-dependent protease. While a
large number of CAPN3 gene mutations have already been described
in calpainopathy patients, the diagnosis has recently shifted from molecular
genetics towards biochemical assay of defective protein.
Methods. Mutation search was conducted using SSCP and direct sequencing
methods.
Rezults. We perform direct sequencing analysis in 8 exons (exons 4,
5,10,11, 12,20, 21 22) in Laboratory of DNA-diagnosis (Moscow) of
patient with clinical features of LGMD,2A. The onset of the disease
is 16-17 age. Involvement was first evident in either the pelvic, with
asymmetry of wasting when the upper limbs were first involved. Spread
from the lower to the upper limbs occurred within 26-27 years. Pseudohypertrophy
of the calves was not established. Biochemical analysis:
elevated levels of serum creatine kinase [hyperCKemia]. By Molecular
-genetics analysis we detected two mutation in heterozygous occurrence
of a missense and deletion mutations: c.550del A (exon 4)
and c.1302C>T (exon 10). These mutations are no conjunction with a
frame-shift mutation. The c.1302C>T mutation did not descript in the
mutation data base. We suggested that this mutation have the important
role in clinical phenotype (compound effect).
Conclusion: Our results illustrate the importance of DNA analysis for
reliable establishment of mutation status, and provide a new insight
into the process of genotype-phenotype correlations of LGMD2A patients.
P0677. Molecular and clinical study of Bulgarian patients
with Limb-girdle muscular dystrophy type 2A (LGMD2A,
Calpainopathy)
B. Georgieva 1 , A. Todorova 1 , T. Todorov 1 , I. Tournev 2 , I. Kremensky 3 , V. Mitev 1 ;
1 Sofia Medical University, Medical Faculty, Department of Chemistry and Biochemistry,
Sofia, Bulgaria, 2 Sofia Medical University, Alexandrovska Hospital,
Department of Neurology, Sofia, Bulgaria, 3 Sofia Medical University, Hospital of
Obstetrics and Gynecology, Laboratory of Molecular Pathology, Sofia, Bulgaria.
A total 24 LGMD2A Bulgarian patients (22 unrelated families) were diagnosed
on DNA. Two of them were reported previous [Richard et al.,
1999]. In about 40% of the cases the first clinical diagnosis was different
from LGMD2, namely DMD/BMD and SMA. The affected females
are two times more than the male patients. Calf hypertrophy, early contractures,
proximal muscle weakness in the four extremities simultaneously,
pelvic/shoulder muscles weakness were more frequently found
in male patients. Females present with later onset, slowly progression,
milder course of the disease, become wheelchair bound later than
male patients. Heart involvement was seen in 2 cases. Interfamilial
and intrafamilial variability were also observed.
We detected 12 CAPN3 gene mutations. Five of them (42%) fall in
exons 4 and 7 and cover 70% (28/44) of the affected unrelated chromosomes.
The most frequent mutations are c.550delA (50%), p.Glu323X (7%)
and the big deletion del2-8 (5%). They were found in 68% (15/22) of the
families and cover 61% (27/44) of the affected chromosomes. The rest
mutations were found in single cases and five of them (p.Arg118Gly,
p.Arg169Gly, p.Gly333Asp, c.1811_1812delTC, c.1981_1984delATAG)
were detected only in Bulgarian patients. In six families the
second mutation was not found.
Calpainopathy occurred the most frequent LGMD2 form in Bulgaria
which accounts for at least 50% of all LGMD2 cases. We developed
a systematic approach for DNA diagnostics of LGMD2A, starting with
mutation screening in exons 4 and 7. The introduced method permits
to perform an adequate prophylaxis of the disease in our country.
P0678. Distinct spectrum of CFTR mutations and IVS8 poly (T)
variants in Persian males with congenital bilateral absence of
the vas deferens
R. Radpour, H. Gourabi, M. Sadighi Gilani, A. Vosough Dizaj;
Reproductive Biomedicine Research Center of Royan Institute, Tehran, Islamic
Republic of Iran.
Congenital bilateral absence of the vas deferens (CBAVD) is a frequent
cause of obstructive azoospermia and nearly 75% of patients
have at least one detectable CFTR mutation. To study the CFTR gene
mutations in Persian CBAVD patients with presumed low cystic fibrosis
(CF) frequency, we analyzed 112 Persian CBAVD and 7 CUAVD males
from Iran with 52 fertile males as control. All 27 exons and their flanking
sequences was analyzed using a combination of the SSCP and
direct sequencing. Forty-six of the 112 patients (41.07 percent) had
two mutations in the CFTR gene, 41 of them had the 5T allele. Fortythree
patients (38.39 percent) had a mutation in one copy of CFTR
gene. In 23 patients (20.53 percent) no CFTR mutations were found.
IVS8-5T was observed with TG12 or TG13 haplotypes, on 61 chromosomes
thus confirming the association of this variant with CBAVD in
Persian patients. Screening for the IVS8-5T and F508del together led
to the identification of more than one-third of alleles. Exon 9 skipping
was strongly joined with 5T/5T genotype, the rate of normal CFTR
mRNA increased by having IVS8-9T (TG) 9-10 and IVS8-7T (TG) 10-11-12 .
We could detect one novel nonsense mutation (K536X) in the NBD1
region and two novel missense mutations (Y122H & T338A) in the M2
and M6 regions of CFTR gene. The combination of the 5T allele in one
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