2008 Barcelona - European Society of Human Genetics

Prenental diagnostics
cal University, Lodz, Poland, 3 Department of Obstetrics and Gynaecology,
“Mother and Child Hospital”, Szczecin, Poland, 4 Dept of Pediatrics “Mother and
Child Hospital”,, Szczecin, Poland, 5 Dept of Pathology Specialistic Hospital
“Zdunowo”, Szczecin, Poland.
A 31 years old gravida was referred at 13 week of pregnancy for prenatal
diagnosis due to previous four undiagnosed pregnancy loss . During
non-invasive screening at 14 week of pregnancy cystic hygroma
(1.33 cm), features of cardiac insufficiency, multiply bone anomalies
and prune belly syndrome suspicion were noted .Urgent karyotype
analyses of both parents with resolution 450 - 650 bb . not detected
any anomalies .Amniocenthesis (with suspicion of X`s chromosomes
anomaly) was performed at 15 week and didn’t detect any pathologies
in classical cytogenetics analyses, but mCGH investigation (2,44 OLI-
GO m-CGH Agilent) showed deletion in 46XY foetus chromosomes of
distal 15q26.1qter and duplication of 3q26.33qter, confirmed by FISH
with use of telomeric probes (Tel Vision 3qSO and 15qSO) and described
as 46XY, ish der (15)t(3;15)(qter+,qter-)pat . Aberration was
result due to next detected paternal balanced subtelomeric translocation
46,XY,ish t(3;15)(qter-qter+;qter+qter-) .In next USG observations
Intrauterine Growth Retardation, hypoplastic long bones, feets and
hands anomalies, heart defect in form of CoA, hypoplastic DA, VSD,
polycystic kidneys and defect of abdominal muscle were diagnosed .
After uuneventful pregnancy a boy (2130g, 40 cm, Apgar 6,6,7) was
born preterm at 36 week . Due to their poor status (particularly renal
anomalies and insufficiency) possibility of cardiosurgery correction
was excluded and he died at 40 day of life.Autopsy confirmed and précised
all detected in foetal USG anomalies and more like: in the heart
aorta-truncus pulmonalis anastomoses, additional perimembranous
VSD, bilateral hydronephrosis with uretheral and urachal hypoplasia
and polysplenia .
P03.56
Total cell free and cell free fetal DNA quantification in
preeclamptic pregnant womans
L. Lazar, B. Nagy, A. Morvarecz, J. Rigó Jr.;
Semmelweis University, Budapest, Hungary.
Background: Presence of cell free fetal DNA in plasma of pregnant
womans is a well known phenomenon . The quantity of DNA is different
in normal and pathological pregnancies . The aim of our study was
to measure and to compare the quantity of total free and fetal origin
DNA in the plasma of preeclamptic patients, and patient with normal
pregnancy and to reveal the correlations with pregnancy age and body
mass index (BMI) in both groups . methods: Blood samples were collected,
and plasma was separated from 71 paeclamptic and 71 patients
witouth simptoms of preeclampsia . Quantitative real-time PCR
analysis of the SRY region of Y chromosome and globin gene was performed
in order to detect and to measure the quantity of cell free fetal
DNA and total free DNA in plasma . Results: The mean pregnancy age
in preeclamptic and control group was 37 and 34 weeks respectively,
BMI ranges between 20 .6-38 .2 and 16 .7-30 . The mean value ± SD, of
total free DNA was: 6 .16E-03±0 .23E-03 ng/mL and 2 .755E-03±0 .32E-
03 ng/mL, in SRY positive cases the quantity of free fetal DNA we
measured 3 .363E-04±1 .28E-05 ng/mL and 1 .04E-04±0 .92E-05 ng/mL
respectively . The diefference between two groups in both cases was
significant (P= .001) . conclusions: The quantity of free DNA is significantly
higher in preeclamptic cases than in patients with normal pregnancy
and depends on mathernal weight . In concordance with other
studies the quantitative measurement of total cell free and cell free
fetal DNA could be a predictive marker in early diagnosis and prevention
of preecalmpsia .
P03.57
Reproductive decision of spanish families with genetic risk for
peroxisomal diseases
T. Pampols 1,2 , M. Coll 1,2 , M. Ruiz 3,2 , M. Girós 1,2 ;
1 Institut de Bioquimica Clinica.Servei de Bioquimica i Genetica Molecular.Hospital
Clinic, Barcelona, Spain, 2 Centro de Investigación Biomédica en Red de
Enfermedades Raras (CIBERER),ISCIII, Barcelona, Spain, 3 Instituto de Investigación
Biomédica de Bellvitge(IDIBELL), Barcelona, Spain.
Peroxisomal disorders are severe neurodegenerative diseases caused
by defects in genes that control single steps of metabolic peroxisomal
pathways as well as the proteins involved in the peroxisomal biogenesis
. Since 1988 we have diagnosed 198 cases of Peroxisomal dis-
eases, 158 of them had been X- linked adrenoleukodystrophy (X-ALD)
, 2 other isolated defects of peroxisomal β-oxidation and 38 defects of
peroxisomal biogenesis (DPB) .
The 158 afected X-ALD/AMN males proceed from 95 families that requested
prenatal diagnosis (PD) in 34 pregnancies . In all the affected
foetuses, parents opted by termination . Couples that were against this
option decided not request PD . In most cases the mother was a carrier
detected in the course of family studies, who proves the relevance of
the recommendation to the parents of the index cases to communicate
the genetic risk to other family members . As far as we know, only in
one case, the couple hide the information to the family, resulting later
on in the birth of one affected child . A couple that undertake 4 pregnancies
with the result of 4 affected male foetuses, requested preimplantatory
sex selection, but they don’t succeed in two consecutive cycles of
in vitro fertilization .
Families with other Peroxisomal disorders asked for DP in 11 pregnancies,
4 at risk for an isolated defect of peroxisomal β-oxidation and 7
at risk for PDB .
P03.58
A case of de novo 16p rearrangement diagnosed prenatally
I. D. Papoulidis 1 , A. P. Athanasiadis 2 , M. B. Petersen 3 , E. Drosopoulou 2 , E.
Siomou 1 , C. Malamaki 1 , F. Partheniou 1 , T. Liehr 4 , Z. G. Scouras 2 ;
1 Eurogenetica S.A., Thessaloniki, Greece, 2 Aristotle University of Thessaloniki,
Thessaloniki, Greece, 3 Institute of child health, Athens, Greece, 4 Institute of human
genetics and anthropology, Friedrich-Schiller-University, Jena, Germany.
A case of a terminated pregnancy of a 30-year-old woman is reported
in which ultrasound examination at 22 weeks’ gestation showed two
umbilical cord vessels, enlarged polycystic right kidney, implying polycystic
kidney disease, and a normal left kidney . Conventional chromosome
analysis (GTG banding) revealed addition of chromosomal
material to the long arm of chromosome 16; however the limited
resolution of conventional prenatal karyotype analysis prevented the
identification of the origin of the additional material. MLPA (Multiple Ligation-dependent
Probe Amplification) analysis was performed, which
showed neither duplication nor deletion in chromosome 16 . Both parents
were found to have a normal karyotype . Expected data will include
Fluorescence In Situ Hybridization (FISH) analysis to identify the
chromosomal origin of the additional material . Furthermore, array CGH
analysis will be performed to define the chromosomal breakpoints and
the size of the additional material .
P03.59
Polyploidy in early spontaneous abortions
I. Tonković Đurišević, D. Mužinić, R. Lasan, K. Crkvenac Gornik, L. Letica, M.
Burek, D. Begović;
Division of Genetics and Metabolism, Department of Pediatrics, University
Hospital Centre Zagreb, Zagreb, Croatia.
Polyploidy is a condition in which there is more than two sets of chromosomes.
A total of 321 cases of first trimester spontaneous abortions
between 4 and 13 weeks of gestation were analyzed cytogenetically by
direct - preparation method using chorionic villi . Among 54% of abnormal
karyotypes, trisomy was predominant . The second most common
abnormality was triploidy found in 25 (7,8%) cases . Triploidy may arise
from fertilization of haploid egg by two haploid sperm or by maternal
or paternal meiotic errors . Tetrapoidy is a rare ploidy abnormality and
was detected in 3 (0,9%) cases, 92,XXYY and 92,XXXX sex chromosome
complement .
Among the triploid abortions the gonosomal constitution of XXY prevailed
(14 cases), followed by XXX (8cases) and XYY (3 cases) . The
maternal age ranged from 18 to 35 age and the gestational age from
6 to 13 weeks . In this study the frequency of poliploidy abortions decreased
with maternal age, what confirms that increased maternal age
is not a risk factor and mechanism of poliploidy .
Triploidy and tetraploidy together account for 18% of chromosomal abnormalities
and give rise to a significant proportion of human pregnancy
wastage . Poliploidyies are numerical abnormalities, are sporadic,
and they do not usually recur in subsequent pregnancies .