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Considerable clinical variability occurs in adult Gaucher disease type I and three main subtypes may be delineated: a very mild form, a severe form, and a moderate form which itself presents various clinical manifestations. A study based on 25 families from our clinic and a review of published reports showed that when both parents were heterozygous and more than one child was affected with Gaucher disease type I, there was always intrafamilial similarity concerning the three subtypes. In families where one parent and at least one child were affected, variability in the clinical subtype of Gaucher disease type I might occur among the affected members of the family. We propose that the three different clinical subtypes of this disease reflect the genetic heterogeneity of two alleles, G1a and G1b and the three corresponding genotypes represent the three different subtypes of the disease. [ABSTRACT FROM PUBLISHER]

Ewing's sarcoma (ES) is the second most common primary malignant bone tumor in children and adolescents. Currently accepted clinical prognostic factors fail to classify ES patients' risk to relapse at diagnosis. We aimed to find a new strategy to distinguish between poor and good prognosis ES patients already at diagnosis. We analysed the gene expression profiles of 14 primary tumor specimens and six metastases from ES patients, using oligonucleotide microarray analysis. The over-expression of two genes was validated by quantitative PCR using the LightCycler system. We identified two distinct gene expression signatures distinguishing high-risk ES patients that are likely to progress from low-risk ES patients with a favorable prognosis of long-term progression-free survival. The microarray-based classification was superior to currently used prognostic parameters. Over-expressed genes in the poor prognosis patients included genes regulating the cell cycle and genes associated with invasion and metastasis, while among the downregulated genes were tumor suppressor genes and inducers of apoptosis. Our results indicate the existence of a specific gene expression signature of outcome in ES already at diagnosis, and provide a strategy to select patients who would benefit from risk-adapted improved therapy.

In the course of positional cloning of the Congenital Dyserythropoietic Anemia type I (CDAI) [MIM 224120] gene on 15q15.1-15.3, we examined a family of French origin, in which the propositus suffered from asthenoteratozoospermia and nonsyndromic deafness in addition to CDAI. Two of his brothers had a similar phenotype. All three siblings were homozygous carriers of the CDA1 mutation as well as of a distally located approximately 70 kb deletion of the proximal copy of a 106 kb tandem repeat on chromosome 15q15. These repeats encode four genes whose distal copies may be considered pseudogenes. Lack of functional stereocilin and CATSPER2 (a voltage-gate cation channel expressed specifically in spermatozoa) may explain the observed deafness and male infertility phenotypes. To the best of our knowledge, the involvement of CATSPER2 in asthenoteratozoospermia is the first description of a human autosomal gene defect associated with nonsyndromic male infertility.

Congenital dyserythropoietic anemias (CDAs) constitute a rare group of inherited red-blood-cell disorders associated with dysplastic changes in late erythroid precursors. CDA type I (CDAI [MIM 224120], gene symbol CDAN1) is characterized by erythroid pathological features such as internuclear chromatin bridges, spongy heterochromatin, and invagination of the nuclear membrane, carrying cytoplasmic organelles into the nucleus. A cluster of 45 highly inbred Israeli Bedouin with CDAI enabled the mapping of the CDAN1 disease gene to a 2-Mb interval, now refined to 1.2 Mb, containing 15 candidate genes on human chromosome 15q15 (Tamary et al. 1998). After the characterization and exclusion of 13 of these genes, we identified the CDAN1 gene through 12 different mutations in 9 families with CDAI. This 28-exon gene, which is transcribed ubiquitously into 4738 nt mRNA, was reconstructed on the basis of gene prediction and homology searches. It encodes codanin-1, a putative o-glycosylated protein of 1,226 amino acids, with no obvious transmembrane domains. Codanin-1 has a 150-residue amino-terminal domain with sequence similarity to collagens and two shorter segments that show weak similarities to the microtubule-associated proteins, MAP1B (neuraxin) and synapsin. These findings, and the cellular phenotype, suggest that codanin-1 may be involved in nuclear envelope integrity, conceivably related to microtubule attachments. The specific mechanisms by which codanin-1 underlies normal erythropoiesis remain to be elucidated.

Background: Growth retardation in childhood was only recently recognized as a prominent feature of Gaucher disease type 1, but there are few data on both the pubertal development and the final outcome of growth and sexual maturation., Objective: To investigate the natural pattern of growth and puberty in patients with Gaucher disease type 1 and the effect of splenectomy and enzyme replacement therapy., Methods: We retrospectively analyzed growth and puberty in 57 patients with Gaucher disease type 1; 52 were followed since childhood and/or prepuberty and 42 have reached sexual maturity and final height. In the analysis we considered severity of disease, time of splenectomy, and start of enzyme replacement therapy., Results: Deceleration of growth at age 3-5 years was observed in 30 of 57 patients followed since early childhood while untreated: height-SDS decreased from -0.34 +/- 0.42 at age 0-3 years to -1.93 +/- 0.95 (P < 0.01) at age 7-10 years and was more pronounced with severe disease. A high prevalence (59.6%) of delayed puberty, which was more frequent with severe disease, was observed in 47 patients followed before and throughout puberty. No primary endocrine pathology was found. All patients, untreated as well as treated, with growth and pubertal delay had a spontaneous catch-up, achieved full sexual maturation, and most (83.3%) reached a final height within the range of parental height-standard deviation score. Splenectomy (partial and/or total) performed in 20 patients while still growing had a beneficial effect on growth, which was temporary in some and did not affect puberty. ERT improved growth in 11 patients who started therapy before puberty, as evidenced by a progressive increase in the height-SDS, and seemed to normalize the onset of puberty., Conclusions: Growth retardation in childhood and delay of puberty are characteristic of Gaucher disease type 1 and are more frequent with severe disease. There is a spontaneous catch-up later in life and most patients reach a final height within their genetic growth potential. Enzyme replacement therapy apparently normalizes growth and possibly also the onset of puberty.

Congenital dyserythropoietic anemias (CDA) are a rare group of red-blood-cell disorders of unknown etiology that are characterized by ineffective erythropoiesis, pathognomonic cytopathology of the nucleated red blood cells in the bone marrow, and secondary hemochromatosis. In CDA type I, bone-marrow electron microscopy reveals characteristic findings in erythroid precursors, including spongy heterochromatin and enlarged nuclear pores. Since the genetic basis of CDA type I is not evident, we used homozygosity and linkage mapping to localize the genetic defect responsible for CDA type I in 25 Bedouins from four large consanguineous families. We report the linkage of this disease to markers on chromosome 15 located at q15. 1-q15.3. Fourteen markers within a 12-cM interval were typed in the relevant family members. Nine of the markers yielded maximum LOD scores of 1.625-12.928 at a recombination fraction of .00. Linkage disequilibrium was found only with marker D15S779. Haplotype analysis revealed eight different carrier haplotypes and highlighted the existence of a founder haplotype. Identification of historical crossover events further narrowed the gene location to between D15S779 and D15S778. The data suggest localization of the CDA type I gene within a 0.5-cM interval. The founder mutation probably occurred >/= 400 years ago. Sequence analysis of the coding region of protein 4.2, the only known erythroid-specific gene in the locus, did not reveal any change in the CDA type I patients. Future analysis of this locus may lead to the identification of a gene essential to normal erythropoiesis.

Screening for p53 mutations in exons 5 to 8 in 124 pediatric malignancies identified 18 abnormal shifts using single strand conformation polymorphism: 12 were missense mutations and in 6, no mutation was detected in the exon or in the splice donor acceptor sequences. Sequencing was then performed in the adjacent introns, revealing a G to A base substitution at 39 base pairs upstream to exon 7. This mutation was identified in the germ line of five of the patients, and also in the father of one, whose parents were available. For comparison, of the 184 normal controls similarly screened, only one had this mutation (P=0.036). Positive staining of p53 protein was observed in three of the paraffin embedded tissues that were available: brain tumor, rhabdomyosarcoma, and lymphocytes from a normal lymph node from the rhabdomyosarcoma patient. All tumors with the identified intron mutation were Li-Fraumeni syndrome tumors. Sequencing of all exons including splice sites was performed and revealed no mutation. We suggest that this mutation in intron 6 of the p53 gene stabilizes the wild type p53 protein, resulting in its abnormal accumulation. Mutations in the noncoding region of p53 should be further studied.

A new large deletion from the human alpha-globin gene cluster is characterized. It involves at least 39 kb and includes the two alpha-globin genes, the theta 1-gene, all the pseudogenes, and the two hypervariable regions (HVRs), interzeta-HVR and alpha-globin 3'HVR. The conserved zeta-globin gene has been identified in various restriction fragments of abnormal size. The new deletion was found in four unrelated Israeli patients with Hb H disease, all originating in Yemen, and has been designated--YEM. It is the only two-gene deletion identified in this ethnic group.

The hemoglobin concentration, red cell count, hematocrit, reticulocyte count, and red cell size distribution were determined on skin prick blood obtained on the first postnatal day from infants born at various stages of gestation, from week 24 to term. During this period the hemoglobin concentration and hematocrit remained constant, around 19 gm/100 ml and 60%, respectively. The mean corpuscular volume decreased progressively, with a corresponding rise in the red cell count. The reticulocyte count decreased progressively from 9.6% to 3.7% during the period of observation. The red cell size distribution (Price Jones) curve was markedly shifted to the macrocytic side at 24-25 weeks. Thereafter, cells larger than 102 mu3 decreased gradually, while the percentage of smaller cells increased. These observations are not consistent with the hypothesis of a progressive decrease in the supply of oxygen to the fetus during the later stages of gestation, to which the fetus adapts by increasing its hemoglobin concentration.