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Polyvalvular heart disease has been reported in a handful of "private" syndromes that have been recently suggested to represent a single dominantly inherited condition, the polyvalvular heart disease syndrome. We report five cases in two unrelated families (one sporadic case in the first family and three siblings and their father in the second family) with the same association of polyvalvular heart disease, distinctive facial appearance, and, except the father in family 2, major joint hypermobility. Interestingly, in three of our patients (2 siblings and the sporadic case), electron microscopy revealed characteristic ultrastructural skin abnormalities with abnormal amorphous or microfibrillar deposits under the capillary basal membrane in the papillary dermis, suggestive of a connective tissue disorder, but different from Marfan syndrome or Ehlers-Danlos syndrome. Moreover, in family 2, three others sibs died in early infancy of their heart defect. Our two families and the other published cases might illustrate intrafamilial and interfamilial variability within a single condition. However, our two families disclose major joint hypermobility, normal stature, and ultrastructural skin abnormalities that were not described in the previous reports. These discrepancies let us to consider them as affected by a distinct disorder of the connective tissue.

High throughput genetic technologies offer the opportunity to gain precision in the diagnosis of numerous diseases and to better understand their molecular basis. However they bring new practical and ethical challenges, some of which are foreseeable and therefore amenable to the timely adoption of strategies to ensure that they are introduced and used in a just and beneficial manner. One way of foreseeing these challenges is to examine technologies that have already been transferred from research to the clinical setting in order to identify the ethical issues and develop strategies to move forward in an ethical way. One such model for new genetic technologies is Array Comparative Genomic Hybridization (aCGH), which has been gradually adopted in recent years as a standard technique in clinical genetics. CGH challenging current clinical practice regarding the detection and diagnosis of human chromosome abnormalities in intellectual disability (ID) and congenital malformations in children. Experience with aCGH has shown that it delivers an unprecedented volume of information for patients, counsellors, and health care providers but it also raises specific ethical challenges which can serve as signposts for potential issues with future, even more detailed, genetic technologies. These issues are described and illustrated through case histories, and their consequences for the patient-clinician relationship in genetic consultation are discussed. The consequences of employing this technology, as compared to the more traditional genetic diagnostic methods used in cases of intellectual disability are categorised into issues linked to 1) the vulnerable nature of patients who are mostly children, mentally retarded people or “future parents”; 2) the way in which information is controlled at each stage of the process, as a function of its potential relevance to the clinical condition being diagnosed, 3) the information related to conditions other than ID or “incidental findings” that become the rule with high throughput technologies. The issues highlighted by the clinical scenarios discussed here can be expected to occur with even greater frequency in the future as whole exome and whole genome sequencing are introduced. Building on our experience with the transfer and adoption of aCGH into clinical genetics, we have developed a grid of points to be considered when translating such technologies from research to clinic.

Background : The normal levels of alkaline phosphatase (AP) activity in maternal serum are virtually the same as those observed in Down syndrome (DS) pregnancies at 14–20 weeks' gestation. Using urea inhibition of AP, we observed an atypical AP isoenzyme in the neutrophils of mothers with trisomy 21 fetuses. Aim : To assess the use of urea as a selective inhibitor of serum AP in order to seek a possible diagnostic difference between normal and DS pregnancies. Study Design and Subjects : Serum AP samples from 24 DS pregnancies and 204 control cases were examined at 12–22 weeks' gestation with and without 2.5 M urea AP inhibition at 18 °C for 2 h. The levels of AP activity obtained without urea and the percentage urea AP inhibition were analyzed in the two groups. Results : Without urea treatment, no significant difference of total alkaline phosphatase activity levels was detected between the 204 normal controls and the 24 DS samples. Using 2.5 M urea AP inhibition, after 120 min of exposure at 18 °C, the residual activity, as a percentage of initial values of AP, showed significantly higher resistance in the DS samples (≥50 IU/l of total AP activity) at 15–22 weeks' gestation. However, at 12–14 weeks (≤45 IU/l of total AP activity), no significant difference was found between the DS and control cases. Conclusion : Serum urea resistant alkaline phosphatase in DS pregnancies showed a significant difference only at 15–22 weeks' gestation, compared with normal controls.

Testicular cancer is the most common neoplasia occurring in the young male population. The PEB (cisplatin, etoposide and bleomycin) adjuvant chemotherapy usually proposed after orchidectomy in non seminomatous tumours, and in metastatic seminomas, has improved the long-term survival of these patients. Following an azoospermic period, sperm cell recovery is generally observed after treatment delivery, but little is known about the genetic consequences on these new spermatozoa. To estimate the chromosomal consequences of this chemotherapy on sperm cells during the period of recovery of spermatogenesis, sperm cell aneuploidy was studied in testicular cancer patients, at 6-18 months after PEB adjuvant chemotherapy delivery, using fluorescence in-situ hybridization (FISH) of chromosomes 7, 16, 18, X and Y with specific DNA probes. A significant increase in the frequency of diploidy and disomy for chromosomes 16, 18 and XY was observed in treated patients compared with a healthy control group. Spermatozoa aneuploidy occurring during the spermatogenesis recovery period might be a possible side effect of the PEB regimen. Thus, practitioners should be advised to provide counselling about the need for an appropriate duration of contraception. Moreover, genetic counselling should be offered in cases of pregnancy occurring soon after the end of chemotherapy.

Microdeletions of the long arm of the Y chromosome (Yq) are a common cause of male infertility. Since large structural rearrangements of the Y chromosome are commonly associated with a 45,XO/46,XY chromosomal mosaicism, we studied whether submicroscopic Yq deletions could also be associated with the development of 45,XO cell lines. We studied blood samples from 14 infertile men carrying a Yq microdeletion as revealed by polymerase chain reaction (PCR). Patients were divided into two groups: group 1 (n = 6), in which karyotype analysis demonstrated a 45,X/46,XY mosaicism, and group 2 (n = 8) with apparently a normal 46,XY karyotype. 45,XO cells were identified by fluorescence in-situ hybridization (FISH) using X and Y centromeric probes. Lymphocytes from 11 fertile men were studied as controls. In addition, sperm cells were studied in three oligozoospermic patients in group 2. Our results showed that large and submicroscopic Yq deletions were associated with significantly increased percentages of 45,XO cells in lymphocytes and of sperm cells nullisomic for gonosomes, especially for the Y chromosome. Moreover, two isodicentric Y chromosomes, classified as normal by cytogenetic methods, were detected. Therefore, Yq microdeletions may be associated with Y chromosomal instability leading to the formation of 45,XO cell lines.

In a search for potential infertility loci, which might be revealed by clustering of chromosomal breakpoints, we compiled 464 infertile males with a balanced rearrangement from Mendelian Cytogenetics Network database (MCNdb) and compared their karyotypes with those of a Danish nation-wide cohort. We excluded Robertsonian translocations, rearrangements involving sex chromosomes and common variants. We identified 10 autosomal bands, five of which were on chromosome 1, with a large excess of breakpoints in the infertility group. Some of these could potentially harbour a male-specific infertility locus. However, a general excess of breakpoints almost everywhere on chromosome 1 was observed among the infertile males: 26.5 versus 14.5% in the cohort. This excess was observed both for translocation and inversion carriers, especially pericentric inversions, both for published and unpublished cases, and was significantly associated with azoospermia. The largest number of breakpoints was reported in 1q21; FISH mapping of four of these breakpoints revealed that they did not involve the same region at the molecular level. We suggest that chromosome 1 harbours a critical domain whose integrity is essential for male fertility.

We report a follow-up of 49 children with acute lymphoblastic leukemia (ALL) diagnosed between 1972 and 1978 (follow-up 12–18 years). This series allowed us to analyze the predictive value of karyotype in a long-term follow-up. Karyotypes were abnormal in 33 cases (67.3%): pseudodiploidy in 11 (22.4%), hyperdiploidy > 50 chromosomes in 8 (16.3%), hyperdiploidy 47–50 chromosomes in 11 (22.4%), and hypodiploidy in 3 cases (6.1%). Event-free survival (EFS) and survival studies showed that the outcome of patients was determined only by treatment and karyotype. Eleven patients have survived, nine in first remission (6 years 5 months to 15 years 2 months), and two are in second remission (3 years 8 months and 8 years 2 months). All ploidy groups are represented in these patients. Late relapses can occur in the hyperdiploid > 50 group, thus accounting for shorter EFS than expected, but because of the unusually long second remission of one patient, the rate of surviving patients was higher for this ploidy group than for all other ploidy groups together. Conversely, patients with only numerical abnormalities (no matter which ploidy group they belonged to), had a better outcome than did patients with structural changes or normal karyotypes and no discrepancy between EFS and survival curves was observed in this chromosomal group. Thus, our results suggest that numerical changes only should be considered an indicator of low risk factor, but our results, based on partially banded karyotypes, need to be verified by a current method and therapy.

The common clinical features reported in ring chromosome 22 cases include overall developmental delay with severe speech disability, growth retardation with frequently associated microcephaly, hypotonia, and dysmorphic traits, such as epicanthus, normally placed but large and dysplastic ears, long eyelashes with full eyebrows, and occasionally high arched palate, dental malocclusion, and mild hypertelorism.1–9 Second and third toe syndactyly, unsteady gait, hyperactivity, aggressive behaviour, autistic disorders,3, 4 and seizures or abnormal EEG1, 2 have also been reported. The recently described subtelomeric 22q deletion syndrome showed overlapping clinical features with a generalised developmental delay, particularly severe in the area of expressive speech.10–14 The phenotype is usually more severe in cases of ring chromosome 22 compared with subtelomeric 22q deletions. The phenotypic differences, particularly the growth retardation with microcephaly and the severe mental delay, could be the result of a larger deletion size in ring chromosome 22 cases. We report the molecular cytogenetic analysis of a ring chromosome 22 in a young boy investigated for global development and severe speech delay. This is the first molecular analysis of a ring chromosome 22 harbouring the second smallest 22qter microdeletion reported so far. Characteristics of cases with ring chromosome 22 and subtelomeric 22q deletion are reviewed. ### Case report The patient, a 7 year old boy, was seen for evaluation of global developmental delay. He was born to healthy, non-consanguineous parents aged 35 (mother) and 39 (father) years. His two older sisters were normal. Pregnancy, delivery, and the neonatal period were uneventful. His birth weight was 3330 g (50th centile), length was 50 cm (25th centile), and head circumference was …

A patient developed a secondary blood disorder 7 years after radiotherapy for a gastric lymphoma. The initial myelodysplastic syndrome evolved to a myeloproliferative phase with transient polycythemia, progressive thrombocythemia, and hyperleukocytosis. Chromosome analysis performed in the terminal phase showed del(5)(q13q31),t(9;22)(q34;q11), and a complex rearrangement involving chromosomes #2 and #3. A correlation between chromosomal abnormalities and hematologic findings could be established. In this case, we have assumed that the Philadelphia translocation is a late event, due to prior mutagen exposure, and its association with a common secondary abnormality (5q−), followed by a progressively developing myeloproliferative phase. Furthermore, the association of Ph and 5q− in a single clone seems to indicate that the same stem cell is affected by these two abnormalities.