Radiosensitivity detected by the micronucleus test is not generally increased in sporadic prostate cancer patients.

The micronucleus test (MNT) has shown increased micronuclei (MN) frequencies in BRCA associated and sporadic breast cancer patients, Ataxia telangiectasia and Nijmegen Breakage Syndrome patients, demonstrating a common cellular phenotype of increased radiosensitivity. Some genes, causative of these diseases, have also recently been associated with prostate cancer. In order to investigate if prostate cancer exhibits the cellular phenotype of increased radiosensitivity, we performed MNT analysis on 22 sporadic prostate cancer patients and 43 male controls. We determined the baseline MN frequency, in order to see in vivo chromosomal damage without radiation, and induced (after irradiation with 2 Gy) frequency of MN, both in binucleated cells (BNC) obtained from cultured peripheral blood lymphocytes. An automated image analysis system was used to score the MN employing two different classifiers (Classifier A and B) for detection of BNC. The mean baseline frequencies were 48/43 MN/1000 BNC (A/B) for the controls and 42/50 (A/B) for prostate cancer patients. The induced MN frequencies amounted to 107/111 MN/1000 BNC (A/B) for controls and 111/114 MN/1000 BNC (A/B) for prostate cancer patients. The obtained MN frequencies did not result in a statistically significant difference between unselected cases and controls. However, restricting the analysis to young patients (50-60 years, N = 7) and age-matched controls (N = 7) revealed marginally significant higher MN frequencies in patients. We conclude that increased radiosensitivity is not a property of prostate cancer patients in general.

Familial iridogoniodysgenesis and skeletal anomalies: a probable new autosomal recessive disorder.

Three sibs with congenital glaucoma, skeletal anomalies, and peculiar facial appearance were studied. At birth, enlarged eyes and corneae were present in the proposita and her two brothers due to congenital glaucoma secondary to iridogoniodysgenesis (IGD). The purpose of this article is to describe the second familial case with IGD and skeletal anomalies as the family previously described by García-Cruz et al. in 1990, corroborating this new distinct dysmorphic syndrome with probable autosomal recessive inheritance.

[The genetic DNA trace in men: chromosome Y haplotypes in a Mexican population, analyzing 5 STRs]. / La huella genética del DNA en varones: haplotipos del cromosoma Y en una población mexicana analizando cinco STRs.

BACKGROUND: Short tandem repeats or STRs on the non-pseudoautosomal region of the Y-chromosome are polymorphic markers used to obtain a specific male DNA profile to unravel special cases in the Legal Medicine casework. Haplotypes of Y-chromosome are constructed by analysis of many STRs. They allow solving paternity cases where the alleged father is not available, as well as forensic situations, as rape cases, where mixtures of male/female DNA are present. METHODS: Five Y-linked STRs recently informed: A4, A7.1, A7.2, A10 y C4 (White et al. 1999) were PCR-typed in 101 mexican mestizos from the Northwest of Mexico by means of native polyacrilamide gel electrophoresis and silver staining. RESULTS: Allelic frequencies were estimated for each STR. Their gene diversity ranged from 57.1% for A-4 to 74.7% for C-4. Excepting for A-4, Mexican Y-chromosome STR allele distributions displayed similarity (p > 0.05) to the previously informed population. Seventy-five different haplotypes were observed from 98 complete haplotypes obtained. The haplotype diversity and the male discriminatory capacity of this five-locus system were 99.0% and 77.5%, respectively. CONCLUSIONS: This knowledge permits to use effectively these five Y-chromosome markers in legal medicine casework in the studied population. This STR-system is a new resource of Y-chromosome polymorphism that offers a great potential to identify males and male-lineages, and can be used confidentially in paternity testing and forensic analysis in Mexican population.

Ring-20-syndrome and loss of telomeric regions.

A patient aged 10 years and 8 months with a ring-20-syndrome was studied. Clinically he presented normal psychomotor development until 25 months of age when he began with right simple partial motor seizures. He presented minimal dysmorphism, generalized tonic-clonic seizures refractory to medical therapy and behavioral troubles. He was submitted to a callosotomy when he presented an electric status, subsequently, he was treated with anticonvulsivants and felbamate and the seizures were controlled. The karyotype showed a chromosomal complement 46,XY,r(20)(p13q13.3) with loss of the telomeric regions evidenced by FISH. The mother had normal karyotype. The clinical and cytogenetic features of previous cases described in the literature were compared leading to a better characterization of this syndrome.