2008 Barcelona - European Society of Human Genetics

Prenental diagnostics
Genotype
Infertile group (N =
189)
Control group (N =
194)
PON55 LL 73 97
ML 93 87
MM 21 10
chi-square(2) 7 .37
p 0 .02
PON192 QQ 98 91
QR 74 90
RR 15 13
chi-square(2) 1 .84
p 0 .40
PON311 SS 106 92
SC 72 85
CC 9 17
chi-square(2) 4 .40
p 0 .11
GSTM1 null 97 92
normal 90 102
chi-square(1) 0 .59
p 0 .44
GSTT1 null 35 46
normal 152 148
chi-square(1) 1 .14
p 0 .29
P02.242
Detection of the most common genetic causes of male infertility
by QF-PcR analysis
D. Plaseska-Karanfilska 1 , T. Plaseski 2 , P. Noveski 1 , S. Trivodalieva 1 , G. D.
Efremov 1 ;
1 Macedonian Academy of Sciences and Arts, Research Centre for Genetic Engineering
and Biotechnology, Skopje, The former Yugoslav Republic of Macedonia,
2 Faculty of Medicine, Clinic of Endocrinology and Metabolic Disorders,
Skopje, The former Yugoslav Republic of Macedonia.
The most common genetic causes of spermatogenic failure are sex
chromosomal abnormalities (most importantly Klinefelter’s syndrome)
and deletions of the azoospermia factor (AZF) regions (AZFa, AZFb,
AZFc) of the Y chromosome . Recently, several studies have proposed
that partial AZFc deletions/duplications may represent a risk factor for
spermatogenic impairment . Here we describe a multiplex quantitative
fluorescent (QF)-PCR method that allows detection of these common
genetic causes and risk factors of male infertility . The 11-plex QF-PCR
included the amplification of amelogenine gene; four polymorphic
X-specific short tandem repeats (STR) markers (XHPRT, DXS6803,
DXS981 and exon 1 of the AR gene), non-polymorphic Y-specific
marker (SRY gene), polymorphic Y-specific STR marker (DYS448),
as well as co-amplification of DAZL/DAZ, MYPT2/MYPT2Y and two
CDY1/CDY2 fragments that allowed for the determination of the DAZ,
MYPT2Y and CDY gene copy number . A total of 348 DNA samples
from infertile/subfertile patients (n=204) and fertile controls (n=144)
were included in the study . We detected 14 infertile males with sex
chromosomal aneuploidies (10 individuals with Klinefelter’s syndrome,
two XX and two XYY males) . All previously detected AZF deletions;
AZFc (n8), AZFb (n1), AZFb+c (n1), gr/gr (n11), gr/gr with b2/b4 duplication
(n3) and b2/b3 (n5) gave a specific pattern with the 11-plex
QF-PCR . In addition, 29 DNA samples showed pattern consistent with
the presence of gr/gr and two with b2/b3 duplication . In conclusion,
multiplex QF-PCR is a rapid, simple, reliable and inexpensive method
that can be used as a first-step genetic analysis in infertile/subfertile
patients .
P03. Prenatal diagnostics
P03.01
Use of array cGH in prenatal diagnosis
H. Raussi1 , P. Miny2 , K. Heinimann2 , F. Wenzel2 , I. Filges2 , A. Godenhjelm1 , P.
Ollikka1 ;
1 2 PerkinElmer LAS, Wallac, Turku, Finland, Division of Medical Genetics, University
Children’s Hospital, Basel, Switzerland.
OBJECTIVE: Microarray based comparative genomic hybridization
(aCGH) is relatively widely used in genetic diagnosis of children, but
true potential is still unexplored in prenatal diagnosis . The objective of
our study is to evaluate the feasibility of BAC arrays in the analysis of
prenatal samples .
METHODS: Chorionic villus and amniotic fluid samples are obtained
using standard clinical procedures . DNA is extracted and labelled for
the aCGH analysis . For samples with limited amounts of DNA, we perform
whole genome amplification (WGA). Two types of arrays are used:
arrays targeted to constitutional syndromes (Constitutional Chip ® 3 .0),
and 1 Mb resolution-arrays covering whole genome (Spectral Chip TM ) .
The arrays are scanned with ScanArray ® , and data is analysed with
SpectralWare ® . All samples are also analysed by conventional karyotyping.
Potential aCGH findings are confirmed with FISH using the corresponding
BAC DNA as probe .
RESULTS: To reduce the turn-around time, DNA is extracted directly
from the samples. For direct amplification, we have compared three
suppliers for their WGA performance . In addition, some cases have
been tested both with native and amplified DNA to address potential
bias caused by amplification. Results are promising, and a larger set
of samples will confirm the best practices.
CONCLUSION: The use of samples without cell culturing combined
with simultaneous detection numerous genomic imbalances can have
great benefit to prenatal diagnosis. The difficulty in discriminating the
pathologic and benign copy-number variations and the possibility to
detect potentially unwanted information will undoubtedly be challenging
for the professionals interpreting the data but also for array manufactures
.
P03.02
sequential and integrated prenatal screening for Down
syndrome
T. K. Kascheeva, Y. A. Nikolaeva, T. V. Kuznetzova, V. S. Baranov;
Ott Institute of Obstetrics & Gynecology, Saint-Petersburg, Russian Federation.
Objective . To compare the integrated test in three variants screening
for prenatal Down syndrome detection: the first trimester combined
screening , sequential screening and integrated screening .
Methods . Ultrasound scanners Aloka SSD-2000 and Medison SA-
8000 Live was applied for 716 singleton pregnancies on 10-13 weeks
of gestation with 265 of them (37%) were after 35 . First trimester biochemical
markers were studied on 9 to 13 weeks of gestation with
Life Cycle system for prenatal screening (Wallac/Perkin Elmer Life and
Analytical Sciences, Finland) . 644 second trimester samples ( 89,9%)
were tested by test- systems products of “Alkor-Bio”, Saint-Petersburg
. Detection rates (DR) and false-positive rates (FPR) were estimated .
Results . Integrated screening has the lowest FPR . All 27 cases of
chromosomal anomalies (including 22 DS cases) were revealed after
prenatal diagnostics with FPR value 13 .6% (1st trimester) . FPR in the
second trimester screening was 23 .4% . FPR for integrated screening
in this group was twice lower - 11 .3% . For young pregnant women FPR
was 2 .9% comparing to 5 .8% FPR after combining screening .
Conclusion . Integrated screening was the safest policy in the high risk
pregnancies. Interpreting the second test but ignoring the first-trimester
markers measurements leads to false risk estimation .
P03.03
An assessment of the use of interphase FisH in prenatal
diagnosis
N. V. Shilova, T. V. Zolotukhina;
Research Centre for Medical Genetics of RAMS, Moscow, Russian Federation.
Interphase fluorescence in situ hybridization (FISH) with different DNA-
probes has been provided more ability to perform chromosomal enumeration
. In our study FISH with AneuVysion kit (Vysis, Abbott) was
applied for detecting of more commonly aneuploidies in 67 (8,6%) from
779 cases of prenatal diagnosis after CVS . Interphase FISH analysis
was carried out when absence or small amount of metaphases took
place in semi-direct samples to avoid of repeated invasive procedure .
Different aneuploidies were diagnosed correctly and rapidly by FISH
in 14 fetuses with phenotypic abnormalities on ultrasound . In other 53
cases fetal aneuploidies were not detected by FISH analysis . In 49 of
them fetuses did not have any ultrasound abnormalities and appeared
normal at birth. Normal fetal karyotypes were confirmed by conventional
cytogenetic analysis on cord blood lymphocytes in 2 cases
with abnormal ultrasound screening (intrauterine growth retardation) .
There was spontaneous termination of pregnancy at 18-19 weeks gestation
in one case with fetal cystic hygroma . In remainder case with