FGFR3 mutation in thanatophoric dysplasia type 1 with bilateral cystic renal dysplasia: coincidence or a new association?

Thanatophoric dysplasia (TD) is a lethal dwarfism condition due to missense mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Examination of TD patients reveals mainly the involvement of the skeletal system and the brain, but also renal and cardiovascular anomalies have been described. We report the prenatal detection of TD type 1 (TD1) associated with bilateral cystic renal dysplasia (CRD) Potter's type II, in which the molecular analysis reveals the typical Arg248Cys substitution in the FGFR3 gene. CRD has not been previously described in TD or other conditions due to FGFR3 mutations, but occurs in Apert syndrome (due to FGFR2 mutations). The possible involvement of renal developmental defect in FGFR3 mutations is discussed.

Bilateral carcinoma in situ of the testis and cystic fibrosis transmembrane conductance regulator (CFTR) mutation in an azoospermic patient with late-onset 21beta-hydroxylase deficiency.

Testicular cancer can impair spermatogenesis. In addition, chemotherapy or radiotherapy used for its treatment further damage testicular function mainly affecting highly proliferating germ cells. The multifaceted etiology of male infertility includes, among others, alterations of male reproductive tract differentiation such as monolateral or bilateral congenital absence of vas deferens and perturbations in adrenal steroid synthesis on a genetic basis such as 21beta-hydroxylase deficiency. Herein, we report the case of a male patient with primary infertility, probably related to a combination of genetic and acquired factors with different expressions over time.

Occurrence of thanatophoric dysplasia type I (R248C) and hypochondroplasia (N540K) mutations in two patients with achondroplasia phenotype.

We report two patients with clinical and radiological findings of achondroplasia, who had the most common FGFR3 mutation occurring in thanatophoric dysplasia type I and hypochondroplasia, respectively. Thanatophoric dysplasia is usually a lethal condition, but the patient carrying this mutation is alive and presents a medical history similar to that of patients with achondroplasia. The events leading to such a discrepancy between genotype and phenotype are unclear. These rare cases may influence an appropriate medical and genetic counseling.

Direct DNA analysis in a new Italian carrier of Hb-Belfast: beta 15 (A12) Trp-->Arg.

A young woman aged 21 was found to be a new carrier of Hb-Belfast: beta 15 (A 12) Trp-->Arg, and the characteristics of her hemoglobinopathy were not different from those of the four cases so far described: mild hemolysis with molecular instability of the abnormal Hb, red cells inclusion bodies, and slight alterations of some functional parameters of whole blood. On this occasion, direct DNA analysis indicated the genomic nucleotide replacement of the disease: TGG-AGG. This was inherited by the mother, originating from Bari (Apulia).

Fontaine-Farriaux craniosynostosis: second report in the literature.

Craniosynostosis is determined by the precocious fusion of one or more calvarial sutures leading to an abnormal skull shape. Additionally, nodular heterotopia is a disorder of neuronal migration and/or proliferation. We describe a very rare multiple congenital anomalies (MCA) syndrome in which craniosynostosis is associated with bilateral periventricular nodular heterotopia (BPNH) of the gray matter and other malformations involving hands, feet, and the gut. Clinical findings and further investigations suggest the diagnosis of craniosynostosis Fontaine-Farriaux type. To the best of our knowledge, this case is only the second report of this MCA syndrome. Based on the clinical and radiological data of the two cases reported, we hypothesize that this malformative complex may be considered a new BPNH/MCA syndrome and propose to classify it as BPNH/craniosynostosis. Previous studies demonstrated that at least two BPNH/MCA syndromes have been mapped to the Xq28 chromosomal region in which a causative gene for isolated BPNH is located. The same authors hypothesized that other BPNH syndromes could be due to microrearrangements at the same Xq28 region. Our case presents several overlapping features with some BPNH/MCA syndromes and it is possible that this new complex disorder may be caused by rearrangements at the same chromosomal region that could alter expression of different genes in Xq28.

Sonographic and molecular diagnosis of thanatophoric dysplasia type I at 18 weeks of gestation.

Thanatophoric dysplasia is the most common type of lethal skeletal dysplasia. It can usually be diagnosed with ultrasound, but differential diagnosis with other osteochondrodysplasias is not always possible. Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene have been demonstrated to cause two distinct subtypes of the disorder. We describe a case of thanatophoric dysplasia type I diagnosed at 18 weeks of gestation by ultrasonography. Genomic DNA obtained by chorionic villus sampling showed a C to G substitution at position 746 in the FGFR3 gene, resulting in a Ser249Cys substitution already known to be associated with type I disease. Implications for perinatal management are discussed.

[Familial Mediterranean fever: report of a case]. / La febbre mediterranea familiare: descrizione di un caso.

Familial Mediterranean fever is an autosomal recessive hereditary disease characterised by recurrent fever, poliserositis, chest and/or abdominal pain. Up to date diagnosis is based on clinical symptoms, familial anamnesis and response to colchicine. It is an inflammatory reaction affecting serosal tissues but until recently different hypotheses have been suggested to explain the greatly increased chemotactic activity of the polymorfonuclear leucocytes. Identification of the function of the MEFV gene on chromosome 16 and its protein allows us to understand the pathogenesis of familial Mediterranean fever as well as provides a new diagnostic test and therapeutic measures. We describe a case of an young patient and review the literature.

A new fast-moving variant causing erythrocytosis and mild hemolysis: Hb Gàmbara [beta 82(EF6)Lys-->Glu].

Hb Gàmbara is a new hemoglobin variant with abnormal beta chains that has been found in three out of four members of a family of Lombardy origin (Gàmbara, Brescia, Northern Italy). The affected subjects led a normal life, but they had modest erythrocytosis and mild (compensated) hemolysis with slight splenomegaly. Their abnormal hemoglobin was about 52% of the total hemoglobin, and was shown to be stable by the isopropanol test. Whole blood P50 of the proband was 19.3 Torr, Bohr effect was decreased (-0.25), as well as the molar ratio between the 2,3-diphosphoglycerate level and total hemoglobin of erythrocytes (0.68). The purified abnormal hemoglobin was characterized by an altered oxygen affinity, low n-factor, chloride, and 2,3-diphosphoglycerate effects. The Bohr effect was about 40% of the normal control. The abnormal hemoglobin moved faster than Hb A at alkaline electrophoresis, and split into two fractions, probably due to the formation of hybrid tetramers (alpha 2 beta A beta X). The reversed phase high performance liquid chromatogram from the tryptic digest of the aminoethylated abnormal beta chain subunits indicated the presence of an extra peptide, beta T-9, 10, replacing the individual peptides beta T-9 and beta T-10. Finally, the proband's DNA, drawn from a suitable segment of the beta structural gene (exon 2), revealed a nucleotide sequence carrying the heterozygous mutation AAG-->GAG at codon 82. This led to a Lys-->Glu substitution at position 82(EF6) of the beta chain.

Identification of Mediterranean beta-thalassemia mutations by reverse dot-blot in Italians and Egyptians.

beta-Thalassemia is a significant public health problem in Egypt where over 1000 of the annual 1.5 million newborns are expected to be affected with this disorder. A preventive program of the disease should be multifaceted with its technical component based on carrier screening and prenatal diagnosis through mutation detection. In addition, it should have an information and educational component with the aim of increasing public awareness of the disease. Proper selection of the technique(s) to be utilized in such a program is highly important. The appropriate technique to be used in screening should be reliable, simple and cost effective. It should also circumvent the problem of marked heterogeneity of the disease in Egypt. The reverse dot-blot technique has been used in the present study for the characterization of mutations in 138 Italian and 108 Egyptian thalassemia chromosomes, confirming its reliability as a screening method. The technique is now in routine use for thalassemia diagnosis in the Microcitemia Center of the Galliera Hospital in Genoa, Italy. Based on these results, we recommend the reverse dot-blot method as the technique of choice in the preventive program of this disease in Egypt.

A novel beta-globin structural mutant, Hb Brescia (beta 114 Leu-Pro), causing a severe beta-thalassemia intermedia phenotype.

This study describes a patient with a thalassemia intermedia-like phenotype in whom beta-globin gene sequencing detected a novel abnormal hemoglobin (Hb) due to a T-C substitution at codon 114 of the beta-globin gene arising as a de novo mutation. The abnormal variant was designated Hb Brescia after the place of birth of the propositus. Normal sequences were detected at the in trans beta-globin locus. In addition, alpha-globin gene analysis detected a triple alpha-globin locus which was inherited from the father. The T-C change at position 114 of the beta-globin gene results in a leucine to proline substitution (Leu-Pro) in the G-helix. The resulting Hb tetramer is highly unstable and precipitates forming inclusion bodies in the peripheral red blood cells. Moreover, the Leu-Pro substitution interferes negatively with the four alpha 1 beta 1 contact points of the G-helix most likely adversely affecting the alpha beta dimer formation. The very severe phenotype presented by our patient is unusual in a heterozygote for an unstable Hb variant and may be explained by the coinheritance of the triple alpha-globin locus.

Expression of the human ETS-2 oncogene in normal fetal tissues and in the brain of a fetus with trisomy 21.

The expression of the ETS-2 proto-oncogene, located on chromosome 21, in normal fetal tissues and in neural tissue of a fetus affected by Down syndrome has been investigated. The results show that the ETS-2 proto-oncogene is expressed in almost all the tissues examined and that it is transcribed at constant levels in neural tissue between the 13th and 24th weeks. ETS-2 expression appeared to be slightly increased in Down syndrome brain compared with that of normal controls of the same gestational age.

EBNA-negative polyclonal B cells derived from a long-term culture of unclassified acute lymphoblastic leukemia: IL-2-like activity of culture's supernatant.

A long-term culture of bone marrow lymphoblasts in a case of unclassified acute lymphoblastic leukemia is described. Cells lacking any lymphocytic marker in the early phase of the culture were gradually substituted by B cells showing a pattern of polyclonality. The culture supernatant contained high levels of immunoglobulins also showing interleukin 2 activity. Search for antigens related to the Epstein-Barr virus was negative. A clonal expansion of B cells versus spontaneous differentiation of unclassified leukemic cells is discussed; the long-term culture technique as a tool for a better evaluation of leukemic cells is suggested and discussed.

[Use of OKT3 monoclonal antibodies and anti-TAC for the quantitative evaluation of interleukin-2]. / Utilizzo degli anticorpi monoclonali OKT3 e anti-TAC per la valutazione quantitativa della interleuchina-2.

OKT3 (10-100 pg/ml) still induces IL-2 responsiveness, while being unable to induce IL-2 production and lymphocyte proliferation, unless exogenous IL-2 is added. This property has been used in order to evaluate and quantify the IL-2 on various cell culture supernatants. Peripheral blood mononuclear cells (MNC) or T cells purified from blood units have been incubated with various concentrations of OKT3 and used as cell target for the quantitation of putative IL-2 containing media. The anti-TAC monoclonal antibody has also been used as internal control in the assay. The procedure suggested seems to be reliable and simpler than the method, currently employed in the IL-2 assay; MNC or T-cells treated with OKT3 proliferate in response to exogenous IL-2 and do not if the anti-TAC monoclonal antibody is previously added. Results are presented and discussed.