2008 Barcelona - European Society of Human Genetics

Cytogenetics
matozoa from carriers of chromosome aberrations allows to understand
peculiarities of meiotic divisions and get information about risk of
conceiving chromosome inbalanced offspring .
FISH with specific DNA probes heteroploidy fraquency was scored in
decondenced sperm from 3 patients with chromosome aberrations:
46,XY,t(2;3)(q33;q29) - case 1; 46,XY,inv(4)(p12q21),inv(10)(p11q21)
- case 2 and 45,XY,der(13;14)(q10;q10) - case 3 .
In case 1 disomy frequency of chromosome involved in this rearrangement
increased (up to 3,01%) . In case 2 disomy frequency of inverted
chromosome (0,9%) was compared to this one the of other autosomes
(1,06% for chromosome 7; 0,9% for chromosome 9) . Frequency of
diploidy was higher in patients with robertsonian (case 3) and recoprocal
translocations (case1) (1,48% and 2,05%, respectively) compared
to patient with invertions (0,54%) . Frequency of heteroploidy are in
agreement with spermiological analysis (WHO standard): patients
46,XY,t(2;3)(q33;q29) and 45,XY,der(13;14)(q10;q10) feature oligoastenozoospermia,
in contrast to patient 46,XY,inv(4)(p12q21),inv(10)(p1
1q21) having astenospermia .
Our data suggest that spermiological analysis can be linked to the
karyotype abberations and carriers of chromosome aberrations with
decrease of sperm concentration have poor fertility prognosis .
Supported by CRDF and RFBR .
P02.225
A Y chromosome with three short arms in a male with a
45,X/46,X,psu dic(Y) karyotype
K. Hansson, K. Szuhai, J. Knijnenburg, F. Hes, E. Bakker, J. Smit, W. vd Ende,
M. Hoogenboom, C. Knepflé, K. Madan;
Leiden University Medical Center, Leiden, The Netherlands.
We report a case with an unusual pseudo-dicentric Y chromosome with
three short arm segments. When the male patient was first referred for
karyotyping because of hypogonadism and mental retardation more
than 30 years ago, he was found to have a mosaic karyotype with two
cell lines, one 45,X and the other with an abnormal non-fluorescent Y
chromosome . The father had a normal Y chromosome . At the age of
47, the patient was referred again for cytogenetic analysis because
of his mental retardation . Mutation analysis in connection with thyroid
dysfunction revealed a thyroid hormone receptor beta (TRb) germline
mutation . FISH studies revealed a complex rearrangement with an
alternating pattern of Y short and long arm material: short-long-shortlong-short
. Using probes for the subtelomeric regions two signals with
the Ypter probe was found whereas no signal was observed with the
subtelomeric Yq probe . Two signals were also found using probes for
the centromeric region and the SHOX gene . In contrast, FISH with
a probe for the SRY gene revealed three signals on the abnormal Y
chromosome: two on the short arms of the dicentric and an extra signal
in the short arm segment situated in the middle of the rearranged
Y chromosome . DNA-studies are in progress to further elucidate the
nature of this complex Y chromosome rearrangement .
P02.226
cytogenetic Analysis of infertile iranian men
S. Soleimani1 , M. Zamaniyan1 , M. Montazeri2 , F. Nasiri1 , F. Mortezapoor1 , M.
Rahnama1 , F. Mahjoobi1 ;
1The Blood Transfusion Organization Research Center, Tehran, Islamic Republic
of Iran, 2NRCGEB, Tehran, Islamic Republic of Iran.
Male infertility factor accounts for about half the cases of couple infertility
.
Some of the chromosomal changes (aberrations) which seem effective
in men infertility include:
1 . Balanced chromosomal translocation
2 . Chromosome inversion
3 . Marker chromosome
4 . Sex chromosome abnormality
Our investigation provides the circumstantial and direct evidences
which confirm the importance of the sex chromosome in reproductive
disorders . We have analyzed (7years study) 845 blood samples from
infertile men which 617 of them were oligospermic and azoospermic .
Constitutional chromosome aberrations were diagnosed in 278 of
these patients . We have observed 29 .2% chromosomal abnormality in
azoospermia men that is compatible with the data from literature .
The following abnormal chromosome complements were found:
46,XX;47XXY;47,XYY;48,XXXY;45,X[10]/46,XY[134];46,XY[4]/
47,XXY[82];
46,XX[11]/47,XXY[36];46,XY[6]/47,XYY[38];46,XY[10]/46,XX[26]/
47,XXY[61];
46,X,del(Y)(q 11 . 23 );46,X,inv(Y)(p 11 . 2 ;q 11 . 22 ) .
We have found some patients with complex structural and aneupoloidy
abnormalities:
× 46,XX,inv(9)(p 11; q 13 )/47,XXY,inv(9)(p 11; q 13 )[4]
× 47,XXY[93]/48,XXY+mar[4]/48,XXXY[2]
× 47,XXY,inv(9)(p 11; q 13 )
× 47,XXY,t(1;17)(p 36 .1; q 21 )
× 46,X,del(Y)(q 11 . 2 )[98]/45,X[6]
× 47,XXY,inv(9)(p 11; q 13 )/t(10;22)(q 26 .3; q 13 .1 )
× 46,X,idic(Y)(p 11 .32 ; q 11 .32 )[27]/45,X[36]/46,XY[2]
We believe that many infertilities especially severe oligospermic and
azoospermic cases raise the need for a cytogenetic analysis besides
molecular techniques to reveal the existence of any genetic abnormalities.
P02.227
meiotic studies in spermatocytes from fertile males
L. Uroz 1 , O. Rajmil 2 , C. Templado 1 ;
1 Unitat de Biologia Cel·lular i Genètica Mèdica, Facultat de Medicina, Universitat
Autònoma de Barcelona, Bellaterra, Spain, 2 Servei d’Andrologia, Fundació
Puigvert, Barcelona, Spain.
BACKGROUND: Meiotic chromosome abnormalities are associated
with male infertility . However, little is known about meiotic process in
men of proven fertility . We carried out meiotic studies in spermatocytes
to establish the base line level of meiotic abnormalities in fertile males .
MATERIAL AND METHODS: Testicular biopsies were obtained from
11 fertile males aged 30-47 . Meiotic spreads were prepared by the airdrying
technique and cells were stained with DAPI . RESULTS: Meiotic
progression was analysed at pachytene, metaphase I and metaphase
II stages, counting 1,000 pachytene spermatocytes per individual . All
males showed a normal meiotic progression, with a proportion of metaphase
II to metaphase I higher than 0 .5 . A total of 848 spermatocytes
at metaphase I was studied . The overall percentage of dissociated sex
chromosomes was 21 .7% . Autosomal synaptic abnormalities were
found in 0 .9% of spermatocytes I (medium-sized bivalents with one
chiasmata or small bivalents as two separated univalents) . Only 0 .2%
of the spermatocytes I analysed were hyperploid . Hypoploidy was not
evaluated, since it could be due to technical artefacts . The percentage
of structural chromosome aberrations per individual ranged from 0% to
5 .8% . The total mean chiasma frequency was 51 .0, ranging from 48 .7
to 53 .0 . CONCLUSION: The incidence of meiotic abnormalities (both
chromosomal and synaptic abnormalities), as well as spermatocyte
distribution and chiasma count in fertile males could be used as reference
data in further studies on males with idiopathic infertility .
Acknowledgements: This work received financial support from The
Generalitat de Catalunya (2005SGR-00495, 2005FI00399)
P02.228
increased autosomal structural aberrations in human
spermatozoa regarding age
C. Templado 1 , A. Donate 1 , J. Giraldo 2 , O. Rajmil 3 , M. Bosch 1 ;
1 Unitat de Biologia Cel·lular i Genètica Mèdica, Facultat de Medicina, Universitat
Autònoma de Barcelona, Bellaterra, Spain, 2 Unitat de Bioestadistica
and Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra,
Spain, 3 Servei d’Andrologia, Fundació Puigvert, Barcelona, Spain.
Background: Although most of de novo structural aberrations are paternal
in origin, little information is avaible on the relationship between
advanced paternal age and structural chromosome abnormalities in
human spermatozoa . Objective: To explore the age effect on the frequency
of structural abnormalities in human spermatozoa . methods:
Fluorescence in situ hybridisation (FISH) with a panel of 62 specific
probes was used in spermatozoa to screen all 22 autosomes for duplications
and deletions . Sperm samples were collected from 10 healthy
males: five males aged 24-37 (mean age 27.8 years) and five males
aged 60-74 (mean age 66 .4 years) . A total of 150,000 sperm nuclei
were scored by multicolour FISH, analysing 1,000 spermatozoa per
donor and per autosome . Results: The frequency of structural abnormalities
per individual ranged from 4 .2% to 7 .8% . The mean percentage
of autosomal duplications was significantly greater (P < .05)
in older donors (4 .5%) when compared with that in younger donors
0