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BACKGROUND: Dysfunctions in the folate metabolism can result in DNA hypomethylation and abnormal chromosome segregation. Two common polymorphisms of this enzyme (C677T and A1298C) reduce its activity, but when associated with aneuploidy studies the results are conflicting. The objective of the present study is to analyze the MTHFR gene polymorphisms in women with Turner Syndrome and in a control group, correlating the findings to the chromosomal aneuploidy. METHODS: The study comprised 140 patients with Turner Syndrome, of which 36 with chromosome mosaicism and 104 non-mosaics, and a control group of 209 fertile and healthy women without a history of any offspring with aneuploidy. Polymorphisms C677T and A1298C were studied by RFLP-PCR and the results were statistically analyzed. RESULTS: The frequency of genotypes MTHFR 677CC, 677CT and 677TT in the patients with Turner Syndrome and chromosome mosaicism was, respectively, 58.3%, 38.9% and 2.8%. Among the patients with non-mosaic Turner Syndrome, 47.1% presented genotype 677CC, 45.2% genotype 677CT, and 7.7% genotype 677TT. Among the 209 individuals of the control group, genotypes 677CC, 677CT and 677TT were found at the following frequencies: 48.3%, 42.1% and 9.6%, respectively. As for polymorphism A1298C, the patients with Turner Syndrome and chromosome mosaicism presented genotypes 1298AA, 1298AC and 1298CC at the following frequencies: 58.3%, 27.8% and 13.9%, respectively. Among the non-mosaic Turner Syndrome patients, genotype 1298AA was found in 36.5%, genotype 1298AC in 39.4%, and genotype 1298CC in 22.1%. In the control group, genotypes 1298AA, 1298AC and 1298CC were present at the following frequencies: 52.6%, 40.7% and 6.7%, respectively. CONCLUSION: No correlation was observed between the MTHFR gene polymorphism 677 and chromosomal aneuploidy in the Turner Syndrome patients. However, the MTHFR gene polymorphism at position 1298, mainly genotype 1298CC that reduces the enzyme efficiency, was more frequent in the group of Turner Syndrome patients, suggesting its involvement in mechanisms related to chromosomal imbalances. INTRODUÇÃO: Disfunções no metabolismo dos folatos podem resultar em hipometilação do DNA e na segregação cromossômica anormal. Dois polimorfismos comuns no gene MTHFR (C677T e A1298C) reduzem a atividade da enzima e, quando associados a estudos de aneuploidias apresentam resultados conflitantes. O objetivo do presente estudo foi a análise dos polimorfismos do gene MTHFR em mulheres portadoras da síndrome de Turner e em indivíduos de grupo-controle, correlacionando os achados ao mecanismo de formação de aneuploidias cromossômicas. MÉTODOS: Foram estudadas 140 portadoras da síndrome de Turner sendo 36 com mosaicismo cromossômico e 104 não-mosaicos, e um grupo-controle composto por 209 mulheres férteis e saudáveis sem história de prole com aneuplodia. Os polimorfismos MTHFR C677T e A1298C foram estudados por RFLP-PCR e os resultados analisados estatisticamente. RESULTADOS: A freqüência dos genótipos MTHFR 677CC, 677CT e 677TT nas pacientes portadoras de síndrome de Turner e mosaicismo cromossômico foi, respectivamente, 58,3%, 38,9% e 2,8%. Das pacientes portadoras de síndrome de Turner não-mosaico, 47,1% apresentaram o genótipo 677CC, 45,2% o genótipo 677CT e 7,7% apresentaram o genótipo 677TT. Nos 209 indivíduos do grupo-controle, os genótipos 677CC, 677CT e 677TT foram encontrados nas seguintes freqüências: 48,3%, 42,1% e 9,6%, respectivamente. Quanto ao polimorfismo A1298C, as portadoras de síndrome de Turner e mosaicismo cromossômico apresentaram os genótipos 1298AA, 1298AC e 1298CC nas seguintes freqüências: 58,3%, 27,8% e 13,9%, respectivamente. Já nas portadoras de Síndrome de Turner não-mosaico, o genótipo 1298AA foi encontrado em 36,5%, o genótipo 1298AC em 39,4% e o genótipo 1298 CC em 22,1% . No grupo-controle, os genótipos 1298AA, 1298AC e 1298CC estavam presentes nas freqüências 52,6%, 40,7% e 6,7%. CONCLUSÃO: Não foi observada correlação entre o polimorfismo C677T do gene MTHFR e a aneuploidia cromossômica presente nas portadoras de síndrome de Turner. O polimorfismo A1298C do gene MTHFR, principalmente o genótipo 1298CC, foi mais freqüente nas portadoras de síndrome de Turner, sugerindo seu envolvimento no mecanismo de formação de aneuploidias cromossômicas.

Short stature is the major characteristic of Turner syndrome. The statural appeal is premature and become evident in the puberty. Haploinsufficiency of SHOX gene has been related as main factor on final height of these patients. Despite the majority of the patients are not growth hormone deficient, the GHr therapy improves the final height. Recently, a great number of publications have described the association between GH and cancer. The cancer risk, in these patients, is mainly associated with the presence of Y chromosome sequences that can lead to the gonadoblastoma development. In conclusion, the GHr therapy in ST patients deserves caution. The investigation of Y chromosome sequences should be performed as well as the prophylactic gonadectomy in the positive cases conferring confidence to the treatment.

Designing a Health Care Service Waste Management Plan, according to the RDC 306 rules, is a responsibility of all those who produce such waste. Since radioimmunoassay (RIA) is one of the most employed techniques, we studied the impact of replacing this technique by liquid chromatography (HPLC) with regard to the reduction of the radioactive residues routinely produced by the Unifesp steroid laboratory. The residues produced by the determination of serum cortisol and 17 alpha-hydroxyprogesterone were classified, and those belonging to groups B and C were evaluated. We observed that, when RIA is used, chemical residues (group B) and radioactive waste (group C) are produced, whereas HPLC generates only chemical residues. Adequation of these techniques showed to be advantageous, by significantly reducing the time of analysis and mainly by eliminating and/or reducing the generation of radioactive waste, encouraging its application to other methodologies, as well as its adoption by other research units.

Gonadal dysgenesis comprises a clinical spectrum of anomalies in patients with female, ambiguous or male phenotype, absent or impaired puberty and karyotype with or without Y chromosome and/or chromosome markers. Although Y-specific sequences are seldom cytogenetically evident, dysgenetic gonads are potentially prone to developing tumors. Gonadoblastoma, a mixed germ cell and sex-cord cells tumor with variable degree of focal calcification, is the most harmful due to its frequency. Other gonadal tumor, malign or not, also occur in gonadal dysgenesis. As they are not metastatic tumors and may be eradicated by selective excisions, the importance of detecting Y-sequences by molecular sensitized techniques is stressed in order to indicate prophylactic gonadectomy.

Precocious thelarche is the breast development before 8 years of age with two peaks of incidence during the first two years of life and after 6 years of age. A 4.75-year-old girl presented with thelarche associated to an excessive intake of phytoestrogens (phye). Tanner development B2P1-2, hormonal levels and pelvic US were compatible with peripheral precocious puberty. During follow-up, a daily intake of soy-based foods was observed (40 mg phye/day). Soy is rich in phytoestrogens, mainly genistein and daidzein. Although phye are less strong than estradiol, its concentration could be from 13,000 to 22,000 times stronger in children fed only by soy-based formulas. Parents were advised and soy intake was reduced to once a week. Progression of pubertal development ceased at B2-3P1. The patient, now 8.66 years old, keeps growing with similar bone and chronological ages. Some questions related to industrial food security, mainly the soy-based food, remain without precise answer. Although it is well known the entity of non-progressive precocious puberty and premature thelarche, pubertal development in this case was strongly related to excessive daily intake of soy and other phye-rich food that could trigger puberty as endocrine disruptor.