Palpebral syringomas and Down's syndrome.

BACKGROUND: Palpebral syringomas have been reported to be more frequent in patients with Down's syndrome than in the normal population. OBJECTIVE: The aim of the present study was to evaluate, in a population of institutionalized patients with Down's syndrome, the prevalence of syringomas and their possible cytogenetic relationships. METHODS: Sixty-one institutionalized patients with Down's syndrome were examined in order to assess the presence of palpebral syringomas. Sixty mentally retarded non-Down's syndrome individuals were used to control group. RESULTS: Fourteen patients, 13 females and 1 male, were found to be affected. The prevalence of syringomas in both sexes was 23%; 42% of all females, and 55% when only adult females were considered, had syringomas. Thirteen of the 14 affected patients had a karyotype of Down's syndrome with free trisomy 21, 1 had a mosaicism 47,XX, +21/46,XX. Histologic examination confirmed the diagnosis in all 4 biopsied cases. A clear-cell pattern was observed only in 1 patient while, sporadically, few tubules showed a central syringial-type cuticula. CONCLUSION: The higher prevalence found in females, as compared to males, can be partially explained by their older age (mean 23.8 vs. 13.9 years). Palpebral syringomas are a common cutaneous pathology in adult females with Down's syndrome.

Evidence of chromosomal fragile sites in schizophrenic patients.

Chromosomal fragility and other chromosomal abnormalities were frequently observed in subjects with neuropsychiatric disorders, such as fragile X syndrome, autism or schizophrenia, but only for the first one the fragility is accepted to be associated to a specific pathology, so that it is used as a diagnostic marker. In this study the authors analyzed 50 schizophrenic males, searching for the rare fragile sites or other aberrations with the method suitable for fra(X) detection. Chromosomes from schizophrenic patients resulted more fragile than those from normal controls, especially chromosome 9. The authors discuss the implications of a possible association of these data with the aetiopathogenesis of schizophrenic syndrome.

C-MYB activation and the pathogenesis of ovarian cancer.

We have detected the expression of the MYB proto-oncogene in ovarian cancer. This oncogene was thought to be expressed in a tissue-specific manner in cells of hematopoietic lineage. Total RNA from three established cell lines and four human primary ovary cancers was examined by Northern and Southern blot, RNAse protection, in situ hybridization and cytogenetic analysis. A 3.8 kb RNA transcript was present in one human primary cell culture which is the same size as that found in the immature myeloid HL60 cell line. No expression was detected in normal ovary tissue. Southern blot analysis of DNA from five ovarian tumors indicated that this gene is not rearranged. Chromosomal analysis of three samples show many abnormalities in two cases and a normal karyotype in another one. The presence of MYB transcript in ovarian cancer suggests that MYB may play a specific role in the pathogenesis of this disease.

Phenotypic and phoniatric findings in mosaic cri du chat syndrome.

We report on mosaic 46,XY/46,XY,del(5)(p15) cri du chat syndrome. The clinical findings are compared with those compiled from a literature survey. A phoniatric evaluation was performed and compared with that of a cri du chat patient without mosaicism previously observed by the authors.

Segregation analysis of autosomal fragile sites in three families with the fragile X chromosome.

Fragile sites on chromosomes 9, at 9p21, 10, at 10q25 and 12, at 12q24, were found in the lymphocytes of some members of three families during the study for detection of a fragile X chromosome. The sites were found to be heritable and folato-sensitive. The genetic implications of these results are discussed.

Prevalence of primary cutis verticis gyrata in a psychiatric population: association with chromosomal fragile sites.

The prevalence of cutis verticis gyrata was studied in a psychiatric institutional population of 494 patients, the majority of whom were mentally retarded or had chronic schizophrenia. Twenty-two subjects (21 males and 1 female) were found to have primary cutis verticis gyrata, yielding a prevalence of about 4.5%. The frequency of the scalp disorder was 11.4% among mentally retarded patients and 1.7% in schizophrenic subjects. A cytogenetic study was performed on patients with primary cutis verticis gyrata. In 9 out of 21 subjects there was evidence of chromosomal fragile sites: 5 patients had fragile sites on the X-chromosome, in 2 there was fragility of chromosome 12 and in 2, fragility of chromosome 9. The fragile X-site is the genetic marker of the 'fragile X-syndrome', a sex-linked inherited disorder often associated with mental retardation and other neuropathological findings.

Subchromosomal localization of two human cytokeratin genes (KRT4 and KRT15) by in situ hybridization.

The genes for human cytokeratins 4 and 15 (KRT4 and 15) are assigned to the p11.2----q12 region of chromosome 12 (cytokeratin 4) and to the q21----q23 region of chromosome 17 (cytokeratin 15), respectively.

Fragile X expression in normal and mentally retarded subjects: effect of treatment with an antifolic agent.

Expression of the fragile site fra(X) (q27.3) in peripheral lymphocytes was evaluated in mentally retarded patients and in normal control individuals before and after administration of the antifolic agent trimethoprim for 7 days. This treatment was effective in converting the status of some individuals from fra(X)-negative to fra(X)-positive. However, the induced level of fra(X) expression was very low and not significantly different in patients and in control subjects and did not increase in those individuals where it was already present before treatment. These data support the contention that fra(X)(q27.3) is a common fragile site and that treatment in vivo with an antifolic agent is not effective in enhancing its degree of expression in vitro. Therefore, such treatment seems to be of no diagnostic value in those cases where the fra(X) syndrome is suspected clinically, but where there is no or very low cytogenetic expression of the fra(X).

Fragile X mental retardation: prevalence in a group of institutionalized patients in Italy and description of a novel EEG pattern.

We have studied the prevalence of the fra (X) and of the autosomal fragile sites fra (10) (q25) and fra (16) (q22) in patients from an institute for the mentally retarded in Italy. We found six cases (1.9%) of fra (10) (q25) and 9 (2.9%) of fra (16) (q22). The study of the fra (X) was restricted to a subgroup of 91 males who did not have other chromosome anomalies or variants, and led to the discovery of 4 fra (X) cases. These 4 had the Martin-Bell syndrome; 3 of them were epileptic and had a characteristic EEG pattern originating during sleep from the temporal lobe not previously described in fra (X) mental retardation.