2008 Barcelona - European Society of Human Genetics

Cytogenetics
tions in 11 persons: t(1,5)(q42 .2;q35 .2) one case, t(8;16)(q22 .2;q13)
one case, t(8;X)(q24 .2;q26) one case, t(7;10)(p22;p12 .1) two
cases, t(8;11)(q22 .3;q13 .5) two cases, t(5;8)(31 .2-ter) one case,
t(17;20)(q12;q11) one case, t(6,11,12) one case, t(3;6)(q21;q23 .2) one
case . The frequency of translocations in our study is similar with those
present in other studies, and was almost equal in males and females .
Knowing the fact that one person is a translocation carrier confirms the
etiology of recurrent miscarriage, and allows us to determine the risk
of recurrence . These couples received the recommendation to perform
amniocentesis in future pregnancies . Both genetic counseling and cytogenetic
analysis should be performed before the application of an
assisted reproductive technology .
P02.119
Identification of chromosomal aberrations in Maruthamalai hills,
coimbatore city, india
L. Balasubramanium, V. Balachandar, R. Sangeetha, K. Suresh, K. Sasikala;
Human Genetics Laboratory, School of Life Sciences, Bharathiar University,
Coimbatore, India.
The aim of the study was to identify dwellers risk of irradiation exposure
in the Maruthamalai hills, Coimbatore . The present study analyzed
levels of chromosomal aberrations, a well-known biomarker of early
biological effects and a predictor of cancer risk . Cytogenetic analyze
has remained the most suitable assay for the evaluation of the genetic
damage induced in somatic cells by clastogens present both in occupational
and environmental settings . Present study seems to be novel
to use for the evaluation of genetic damage in dwellers of Maruthamalai
hills, simultaneously the conventional cytogenetic analysis as well
as identify the radiation level by assessing the thermo luminescence
dosimetry (TLD) . TLD were sent by mail to residents who requested
the radiation survey . In the present study 54 experimental subjects
were selected and equal number of controls also selected . After signing
a consent form, both cases (experimentals and controls) provided
a blood sample (5 ml) to establish cell cultures . Using the conventional
cytogenetic analysis, chromosomal- type and chromatid - type aberrations
were observed in some experimental cases . Dicentrics and
acentric fragments are unstable types of aberrations but in the present
study have not observed any of this aberration in experimentals .
Finally, present study may conclude that low-doses of ionizing radiation
are exposed do not represent by themselves any significant risk of
genetic damage as measured by the conventional cytogenetic analysis
.
P02.120
clinical manifestation of chromosome 2 long arm deletion:
report of five cases presentation of four cases
L. Míguez Alvarez 1 , A. Escalona 2 , M. Santos 2 , C. Hernando 2 , A. González-
Meneses 3 , A. Plaja 4 , C. Fuster 1 ;
1 Fundación Pública Galega de Medicina Xenómica. Unidade de Diagnose
Prenatal. Hospital Clínico Universitario, Santiago de Compostela, Spain, 2 Unitat
de Biologia Cel·lular i Genètica Mèdica. Facultat de Medicina. Universitat
Autònoma de Barcelona, Barcelona, Spain, 3 Unidad de Dismorfología. Hospital
Virgen del Rocío de Sevilla, Sevilla, Spain, 4 Unitat de Genètica. Hospital Materno-Infantil
de la Vall d’Hebron, Barcelona, Spain.
Terminal and interstitial deletion of the long arm of chromosome 2
belongs to the most common structural chromosomal aberrations .
Clinical manifestations of this syndrome comprise: global psychomotor
delay, moderate to severe mental retardation with specific facial
dimorphism. We report the characteristics of clinical features in five
cases of terminal or interstitial deletions in 2q32 .2q35, 2q33q34, 2q36,
2q37 and 2q37.3 identified in conventional G banding, fluorescent in
situ hybridization (FISH) and High Resolution Comparative Genome
Hybridization (HR-CGH) techniques . In one case the deletion of subtelomeric
region of chromosome 2 (2q37 .3) was added to 2q34q37 .2
duplication . A comparison was made of clinical symptoms present in
our patients with relevant data concerning other cases of 2q monosomy
reported in literature in order to establish an accurate phenotypegenotype
correlation and proper genetic counselling of these families .
P02.121
chromosome 9: Deletion Duplication of chromosome 9
Phenotype karyotype correlations case Reports brief review
D. S. Krishna Murthy;
Microtest Innovations Pvt Ltd, Bangalore, India.
Chromosme 9 is exhibits marked heteromorphism and pericentric inversion
. Deletion of chromsome 9p presents with characteristic phenotype
soccassionally with overlapping features of Down syndrome .
Terminal deletion of 9- was first reported by Alfi et al., Deletion 9p is
a rare syndrome. We report here clinical and cytogenetic fidnings in
two cases of deletion 9p and two case sof partial trisomy 9 . resulting
familial translocation (t8p9q)mar and a balanced de novo translocation
t(Yq;9p) .
The clinical finding is correlated with karyotypes and compared with
other reported cases in the literataure .
A brief review of literature of deletion duplication of chromosome 9 will
be presented .
P02.122
combined interstitial duplication 11q22q23 and deletion of
11q24.3: report of a case.
A. Plaja 1 , A. Escalona 2 , T. Vendrell 1 , B. Fernández 1 , A. Fernández 1 , M. Carboneras
1 , C. Fuster 2 ;
1 Programa de Medicina Molecular i Genètica. Hospital Vall d’Hebron, Barcelona,
Spain, 2 Unitat de Biologia Cel·lular i Genètica Mèdica. Facultat de Medicina.
Universitat Autònoma de Barcelona, Barcelona, Spain.
Background: Detection of abnormal karyotypes with associated clinical
manifestations is an important tool for the identification of chromosome
regions with genes that confer susceptibility to genetic disorders .
Objective: Identified the extra material present in a de novo 46,XY,add
(11)(q24 .1) karyotype from a chid with mental retardation, ocular malformations,
mild dimorphic faces, thrombocytopenia and hypogammaglobulinemia
.
Methodology: Conventional cytogenetics, High Resolution Comparative
Genome Hybridization (HR-CGH), FISH with BAC probes .
Results: The HR-CGH profiles showed the gain of 11q22q23 and deletion
of 11q24 .3 chromosome bands . Revaluation of G-banded chromosome
spreads and FISH with BAC probes across the region confirmed
CGH results .
Conclusion: Partial 11q trisomy is unusually in Prenatal and Postnatal
Diagnosis . In most cases is associated with 11q/22q translocation and
a 3:1 meiotic disjunction with 47 chromosomes . The presence of the
pure dup (11)(q22q23) in our patient provide an opportunity to delineate
the phenotypic features due this partial trisomy, since deletion of
11q24 .3 associated phenotypic features are well known .
This work was supported by MCYT (SAF 2003-03894)
P02.123
Hidden chromosome instability in peripheral blood lymphocytes
of unexposed and irradiated persons revealed by means of “G2
bleomycin sensitivity assay”
M. A. Pilinskaya, S. S. Dibskiy, Y. B. Dibskaya, L. R. Pedan;
Research Centre of Radiation Medicine, Kijiv, Ukraine.
With help of modifying “G 2 -bleomycin sensitivity assay” (treatment
of human peripheral blood lymphocytes culture in late post-synthetic
phase of mitotic cycle by bleomycin in concentrations 0,05 and 5,00
mcg/ml) the investigation of hidden chromosome instability in 9 unexposed
donors and in 32 persons with different intensity of radiation
exposure (Chernobyl liquidators including patients with acute radiation
syndrome - ARS) had been fulfilled. Main criterion of chromosomes’
sensitivity to bleomycin exposure total frequency of chromosome aberrations
had been considered . In all examined groups individual levels
of chromosome injuries under identical mutagenic exposure varied in
wide range and didn’t depend on their initial values in intact cultures .
In control donors and in 10 liquidators with low radiation exposure the
mean-group frequencies of induced chromosome aberrations were
quite the same under both testing concentrations of bleomycin . Among
control donors and liquidators three by three hypersensitive persons
had been identified with aberrations’ rates 35.0, 34.0, 16.0 and 34.5,
20 .0 19 .3 per 100 cells, accordingly that can be considered as genetically
caused phenomenon . In 19 ARS patients increased mean-group
frequencies of aberrations induced by bleomycin in both concentrations
had been revealed - 16 .80±0 .50 (8 .7 - 38 .2) and 28,04±0,63 (6 .0