A low rate of trisomy 21 in twin-pregnancies: a cytogenetics retrospective study of 278 cases.

From January 1st 1990 until December 31st 2001, we collected 19686 prenatal diagnosis (on amniocentesis and chorius villus sampling). Five hundred twelve samples (2.6%) concerned 278 twin pregnancies.

Major decrease in the incidence of trisomy 21 at birth in south Belgium: mass impact of triple test?

In South Belgium (Wallonia), the 'triple test' was introduced in 1990-1991, and is nowadays a widely accepted screening method for assessment of trisomy 21 risk in pregnancy. The 'triple test' is not regulated and can be freely performed by any biomedical lab, making epidemiological data unavailable. By contrast, cytogenetic investigations are limited to a few genetic centres, and accurate statistics can be easily built from their files.

Inv(12)(q15q24): a nonrandom change associated with myelodysplasia?

A patient with refractory anemia and a paracentric inversion of chromosome 12, inv(12)(q15q24), is described. This is the second reported case with this chromosome anomaly, suggesting that this rearrangement is a rare but nonrandom change associated with myelodysplastic syndromes.

Deletion of the 5'-ABL region: a recurrent anomaly detected by fluorescence in situ hybridization in about 10% of Philadelphia-positive chronic myeloid leukaemia patients.

Inclusion of the BCR-ABL ES probe in routine cytogenetics led to the identification of a subgroup of Philadelphia positive (Ph+) chronic myeloid leukaemia patients characterized by a 5'-ABL deletion. This anomaly was observed in 5/51 cases (9.8%).

[Genetic counseling and prenatal diagnosis].

Fetal medicine is in full expansion thanks to the tremendous progress made in both fetal access techniques and genetic analysis. In this article, we discuss the role of the genetician within a group of prenatal diagnosis and his contribution to the assessment of fetal diagnosis and prognosis. We describe the different approaches (invasive and non invasive) to fetal investigation i.

Translocation (2;3)(p21;q26) as the sole anomaly in a case of primary myelofibrosis.

Translocation t(2p;3q) is a rare but recurrent finding in myeloid disorders. We present the first case of primary myelofibrosis with t(2;3)(p21;q26) as the sole chromosomal anomaly. The comparison with the 11 other previously published myeloid-associated t(2p;3q) cases confirms that this nonrandom translocation involves a pluripotent stem cell and is associated with a poor prognosis.

Loss of the Y chromosome in bone marrow cells: results on 1907 consecutive cases of leukaemia and preleukaemia.

Loss of the Y chromosome with a resulting 45, X0 karyotype is observed in normal bone marrow cells of elderly males but also in haematological malignancies. Whether Y loss in neoplastic cells is related to the process seen in normal ageing or is part of the carcinogenic process is unknown. The present study concerns the cytogenetic data from 1907 consecutive leukaemic or preleukaemic male patients with special regard to the presence or absence of the Y chromosome.

Genetic risk in natural and medically assisted procreation.

Current in vitro fertilization techniques (IVF) including intracytoplasmic sperm injection (ICSI), microepididymal sperm aspiration (MESA) or testicular sperm extraction (TESE) clearly prevent any spontaneous choice of ova or spermatozoa. According to the widely admitted concept of gamete selection, pregnancies following IVF, when compared to natural fertilization, could therefore present a higher risk of genetic anomalies. However, no increased fetal or newborn abnormalities are noticed with IVF, except perhaps for sex chromosome aneuploidies.

Mutation analysis of the MEN1 gene in Belgian patients with multiple endocrine neoplasia type 1 and related diseases.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by tumors in parathyroids, enteropancreatic endocrine tissues, anterior pituitary, and other tissues. The gene for MEN1 has recently been cloned and shown to code for a 610-amino acid protein of enigmatic function which probably acts as a tumor suppressor. Several mutations causing the MEN1 phenotype have been recently identified.

[Programs of systematic screening in neonatology. Pharmaco-economic aspects].

Systematic neonatal screening offers many advantages for the patients, its family and the community. The Genetic center of the University Hospital of Liège provides neonatal screening for the following diseases: phenylketonuria, congenital hypothyroidy, cystic fibrosis, alpha-1-antitrypsin, adrenal hyperplasia and biotinidase deficiency. On economical grounds, it is clear that the organisation of neonatal screening costs less to the community than the cost of the disease if diagnosis is made too late as to allow an alleviation, or even a total recovery, of the symptomatology.

Private multiple congenital anomaly syndromes may result from unbalanced subtle translocations: t(2q;4p) explains the Lambotte syndrome.

In 1990, Lambotte syndrome was reported as an apparently autosomal recessive multiple congenital anomaly/mental retardation (MCA/MR) syndrome observed in 4 of 12 sibs from a probably consanguineous mating [Verloes et al., Am J Med Genet 1990; 37:119-123]. Major manifestations included intrauterine growth retardation (IUGR), microcephaly, large soft pinnae, hypertelorism, beaked nose, and extremely severe neurologic impairment, with holoprosencephaly in one instance.

Nosology of lysosomal glycogen storage diseases without in vitro acid maltase deficiency. Delineation of a neonatal form.

We describe a boy with an early lethal hypertrophic vacuolar cardiomyopathy of neonatal onset. Abnormal intra- and extralysosomal glycogen storage disease was demonstrated in heart and skeletal muscles. Glycogen content was twice the normal in muscles and over 3-fold the normal in the heart.

Microcephaly, muscular build, rhizomelia, and cataracts: description of a possible recessive syndrome and some comments on the use of electronic databases in syndromology.

We report on a 7-year-old boy born of consanguineous parents with severe microcephaly (-5 SD) but borderline intelligence, juvenile cataract, muscular build, rhizomelic shortness of limbs predominantly of femora, advanced bone age, and micropenis. This combination of signs appears unique and may represent an undescribed, possibly autosomal recessive MCA syndrome. The use of LDDB and POSSUM in the workup of such "new syndromes" is reviewed.

Recurrence of neonatal haemochromatosis in half sibs born of unaffected mothers.

We report two families in which neonatal haemochromatosis was observed in half sibs. In the first family, two successive girls were born of different fathers. In the second family, an affected brother and sister were followed by an affected half brother born after donor insemination.

Microcephaly, macrotia, unusual mimics and mental retardation syndrome: new syndrome or variant of De Lange type 2 syndrome.

We report a boy who shows a severe microcephaly, with mild mental retardation and hypotonia, and a dysmorphic facies: (flat profile, arched eyebrows, mild ptosis, short nose with raised basis, large tip and anteverted nares, long, smooth philtrum, narrow mouth with down turned corners, very large, backward tilted ears, with a prominent lobule, retrognathism and very small and widely spaced, although normally shaped teeth. Vesicoureteral reflux was present. The mother showed similar aspect, large ears, and a grinning smile.

A new form of skeletal dysplasia with amelogenesis imperfecta and platyspondyly.

We report two patients, born of consanguineous parents, affected by a disorder resulting in mild growth retardation. Hallmarks are amelogenesis imperfecta (absence of the enamel cap) associated with brachyolmia-like anomalies: platyspondyly with short pedicles, narrow intervertebral and interpedicular distances, rectangular-shaped vertebrae with posterior scalloping and herniation of the nuclei, and broad femoral necks. Inheritance appears to be autosomal recessive.

Cytogenetic study of bovine oocytes matured in vitro.

Described in the present paper is a cytogenetic study of bovine oocytes matured in vitro. The cumulus-oocyte complexes (COC), punctured from ovaries recovered in a local slaughterhouse, were classified into 3 groups according to follicular diameter 1 to 4mm, 5 to 8mm and 9 to 13 mm. Metaphases available for observation were classified as metaphase I, haploid and diploid metaphase II.

Nuclear lesions during rat hepatocarcinogenesis. II. Measuring the micronuclei during initiation, promotion and progression of rat hepatocarcinogenesis induced with diethylnitrosamine.

We reported in our companion paper the strong correlation between elevated sister-chromatid exchange (SCE) frequencies and the initiation step of rat hepatocarcinogenesis. We have also shown that SCEs return to normal values during the promotion and the progression stages. In the present study, we evaluated the clastogenic activity of diethylnitrosamine (DEN) during initiation, promotion and progression of rat hepatocarcinogenesis.

Nuclear lesions during rat hepatocarcinogenesis. I. Measuring the sister-chromatid exchanges during initiation, promotion and progression of rat hepatocarcinogenesis induced with diethylnitrosamine.

Cytogenetic endpoints such as sister-chromatid exchanges (SCEs), chromosomal aberrations and micronuclei (MNs) have been widely used as indicators of genetic damage. However, no systematic attempts have been made to correlate the levels of these cytogenetic endpoints with the different steps of carcinogenesis. In the present report, the induction, accumulation and persistence of SCEs and high frequency cells (HFCs) were measured in liver cells during the initiation, promotion and progression steps of rat hepatocarcinogenesis induced by diethylnitrosamine (DEN).

Clinical overlap of Beckwith-Wiedemann, Perlman and Simpson-Golabi-Behmel syndromes: a diagnostic pitfall.

We report on a child who died in the neonatal period. Major external anomalies included foetal overgrowth, macroglossia, and ambiguous genitalia (micropenis and perineoscrotal hypospadias with cryptorchidism). Necropsy showed a large right diaphragmatic hernia, visceromegaly, multicystic kidney dysplasia, Langerhans islet hyperplasia, nephroblastomatosis, multiple adrenal adenomas, and dysplastic testicles.

Aneurysms of the abdominal aorta: familial and genetic aspects in three hundred thirteen pedigrees.

Purpose: Familial clustering of abdominal aortic aneurysm was first noticed in 1977.

Methods: Through questionnaire and phone inquiry, familial data on 324 probands with abdominal aortic aneurysms allowed the establishment of 313 multigenerational pedigrees including 39 with multiple affected patients.

Results: There were 276 sporadic cases (264 men, 12 women); 81 cases belonged to multiplex pedigrees (76 men; 5 women).

A prenatal trisomy 21 screening program using alpha-fetoprotein, human chorionic gonadotropin, and free estriol assays on maternal dried blood.

Objective: The feasibility of large-scale Down syndrome maternal screening with dried blood samples and nonradioactive methods was examined.

Study Design: A prospective observation study was performed on a nonselected population of 11,241 pregnant women sampled between January 1991 and September 1992, between 14 and 24 weeks' gestation (ultrasonographic scanning available for 91.6%), through a multicenter collaborative network.