Characterization of endocrine features and genotype-phenotypes correlations in blepharophimosis-ptosis-epicanthus inversus syndrome type 1.

OBJECTIVE: Blepharophimosis syndrome (BPES) is an autosomal dominant genetic condition resulting from heterozygous mutations in the FOXL2 gene and clinically characterized by an eyelid malformation associated (type I) or not (type II) with premature ovarian failure. The distinction between the two forms is critical for female patients, as it may allow to predict fertility and to plan an appropriate therapy. Identifying an underlying causative mutation is not always predictive of the clinical type of BPES since genotype-phenotype correlations are not yet fully delineated. Here, we describe the clinical and hormonal phenotypes of three female patients with BPES type 1 from two novel families, correlate their phenotypes with identified mutations, and investigate the effects of hormone replacement therapy (HRT). METHODS: Clinical, biochemical, and genetic evaluation were undertaken in all the patients and genotype-phenotype correlation was analyzed. The effects of substitutive hormonal therapy on secondary sexual characteristics development and induction of menarche were evaluated. RESULTS: All patients presented with primary amenorrhea or other signs of ovarian dysfunction. Two distinct mutations, a missense p.H104R change and an in-frame p.A222_A231dup10 duplication in the FOXL2 gene were identified. Observed phenotypes were not in accordance with the prediction based on the current genotype-phenotype correlations. HRT significantly improved secondary sexual characteristics development, as well as the induction of menarche. CONCLUSIONS: This study highlights the importance of early recognition of BPES and emphasizes the need of personalized therapy and follow-up in female patients carrying distinct FOXL2 mutations.

MODY type 2 P59S GCK mutant: founder effect in South of Italy.

Mutations in the glucokinase (GCK) gene are the most frequent cause of maturity onset diabetes of the young (MODY) in Italy. We evaluated GCK mutations in 32 unrelated patients younger than 18 years who had been diagnosed with MODY. Eleven different GCK heterozygous mutations were identified in 22 (68.7%) of the 32 probands. Nine mutations were missense and two were nonsense. Three of these mutations (E17X, P59S and E372X) have not been described previously and were shown to be associated with hyperglycaemia. Several prediction methods suggested that the E17X and E372X mutations result in a premature truncated protein and that the P59S mutation is pathogenic. This idea was further supported by evidence suggesting that Proline 59 is a highly conserved amino acid residue and that the P59S mutation does not appear to be present in non-diabetic controls and in sequence variant databases. Furthermore, this mutation was found in six (27.3%) of the patients from the same geographical area, Gargano, pointing to the existence of a founder effect, which was confirmed by microsatellite analysis.

A novel microdeletion syndrome at 3q13.31 characterised by developmental delay, postnatal overgrowth, hypoplastic male genitals, and characteristic facial features.

BACKGROUND: Congenital deletions affecting 3q11q23 have rarely been reported and only five cases have been molecularly characterised. Genotype-phenotype correlation has been hampered by the variable sizes and breakpoints of the deletions. In this study, 14 novel patients with deletions in 3q11q23 were investigated and compared with 13 previously reported patients. METHODS: Clinical data were collected from 14 novel patients that had been investigated by high resolution microarray techniques. Molecular investigation and updated clinical information of one cytogenetically previously reported patient were also included. RESULTS: The molecular investigation identified deletions in the region 3q12.3q21.3 with different boundaries and variable sizes. The smallest studied deletion was 580 kb, located in 3q13.31. Genotype-phenotype comparison in 24 patients sharing this shortest region of overlapping deletion revealed several common major characteristics including significant developmental delay, muscular hypotonia, a high arched palate, and recognisable facial features including a short philtrum and protruding lips. Abnormal genitalia were found in the majority of males, several having micropenis. Finally, a postnatal growth pattern above the mean was apparent. The 580 kb deleted region includes five RefSeq genes and two of them are strong candidate genes for the developmental delay: DRD3 and ZBTB20. CONCLUSION: A newly recognised 3q13.31 microdeletion syndrome is delineated which is of diagnostic and prognostic value. Furthermore, two genes are suggested to be responsible for the main phenotype.

Multiple spinal ganglioneuromas in a patient harboring a pathogenic NF1 mutation.

Ganglioneuroma is a rare benign tumor originating from autonomic ganglia and is considered the benign counterpart of neuroblastoma. Ganglioneuromas may be present as an isolated finding and, rarely, in association with neurofibromatosis type 1 (NF1). However, ganglioneuromas of the cervical spine with intradural extension and multiple locations are extremely rare. We describe a 32-year-old woman with multiple ganglioneuromas of the cervical, dorsal and lumbar spine associated with a few café-au-lait spots and subcutaneous nodules. The patient lacked other NF1 stigmata, such as freckling, Lisch nodules and cutaneous neurofibromas. Although our patient did not fulfill the NF1 diagnostic criteria, molecular diagnosis revealed a pathogenic mutation in the NF1 gene. Approximately 30 patients affected by NF1 and ganglioneuromas have been reported: in all these individuals, NF1 diagnosis was made according to the clinical diagnostic criteria and no patients have molecular diagnosis. Therefore, this is the first case with multiple spinal ganglioneuromas associated with a pathogenic NF1 mutation.

Cryptic deletions are a common finding in "balanced" reciprocal and complex chromosome rearrangements: a study of 59 patients.

Using array comparative genome hybridisation (CGH) 41 de novo reciprocal translocations and 18 de novo complex chromosome rearrangements (CCRs) were screened. All cases had been interpreted as "balanced" by conventional cytogenetics. In all, 27 cases of reciprocal translocations were detected in patients with an abnormal phenotype, and after array CGH analysis, 11 were found to be unbalanced. Thus 40% (11 of 27) of patients with a "chromosomal phenotype" and an apparently balanced translocation were in fact unbalanced, and 18% (5 of 27) of the reciprocal translocations were instead complex rearrangements with >3 breakpoints. Fourteen fetuses with de novo, apparently balanced translocations, all but two with normal ultrasound findings, were also analysed and all were found to be normal using array CGH. Thirteen CCRs were detected in patients with abnormal phenotypes, two in women who had experienced repeated spontaneous abortions and three in fetuses. Sixteen patients were found to have unbalanced mutations, with up to 4 deletions. These results suggest that genome-wide array CGH may be advisable in all carriers of "balanced" CCRs. The parental origin of the deletions was investigated in 5 reciprocal translocations and 11 CCRs; all were found to be paternal. Using customized platforms in seven cases of CCRs, the deletion breakpoints were narrowed down to regions of a few hundred base pairs in length. No susceptibility motifs were associated with the imbalances. These results show that the phenotypic abnormalities of apparently balanced de novo CCRs are mainly due to cryptic deletions and that spermatogenesis is more prone to generate multiple chaotic chromosome imbalances and reciprocal translocations than oogenesis.

Cord blood in vitro expanded CD41 cells: identification of novel components of megakaryocytopoiesis.

BACKGROUND: Megakaryopoiesis represents a multi-step, often unclear, process leading to commitment, differentiation, and maturation of megakaryocytes (MKs) that release platelets. AIM: To identify the novel genes that might help to clarify the molecular mechanisms of megakaryocytopoiesis and be regarded as potential candidates of inherited platelet defects, global gene expression of hematopoietic lineages was carried out. METHODS: Human cord blood was used to purify CD34+ stem cells and in vitro expand CD41+ cells and burst-forming unit-erythroid (BFU-E). We investigated the expression profiles of these three hematopoietic lineages in the Affymetrix system and selected genes specifically expressed in MKs by comparing transcripts of the different lineages using the dchip and pam algorithms. RESULTS: A detailed characterization of MK population showed that 99% of cells expressed the CD41 antigen whereas 73% were recognizable as terminally differentiated fetal MKs. The profile of these cells was compared with that of CD34+ cells and BFU-E allowing us to select 70 transcripts (MK-core), which represent not only the genes with a well-known function in MKs, but also novel genes never detected or characterized in these cells. Moreover, the specific expression was confirmed at both RNA and protein levels, thus validating the 'MK-core' isolated by informatics tools. CONCLUSIONS: This is a global gene expression that for the first time depicts a well-characterized population of cord blood-derived fetal MKs. Novel genes have been detected, such as those encoding components of the extracellular matrix and basal membrane, which have been found in the cytoplasm of Mks, suggesting that new physiological aspects of MKs should be studied.