Tetrasomy 15Q11-Q13 identified by fluorescence in situ hybridization in a patient with autistic disorder

We report a female child with tetrasomy of the 15q11-q13 chromosomal region, and autistic disorder associated with mental retardation, developmental problems and behavioral disorders. Combining classical and molecular cytogenetic approaches by fluorescence in situ hybridization technique, the karyotype was demonstrated as 47,XX,+mar.ish der(15)(D15Z1++,D15S11++,GABRB3++,PML-). Duplication of the 15q proximal segment represents the most consistent chromosomal abnormality reported in association with autism. The contribution of the GABA receptor subunit genes, and other genes mapped to this region, to the clinical symptoms of the disease is discussed.

Papilomavírus humano (HPV) em lesões benignas e malignas de mucosa oral pelos métodos de imuno-histoquímica e hibridização in situ

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Short interspersed repetitive elements (SINEs) from the cichlid fish, Oreochromis niloticus, and their chromosomal localization by fluorescent in situ hybridization

In the present study, we describe the cloning and characterization of a new SINE-like element from O. niloticus (ROn-2) and show the distribution of this SINE and a previously isolated SINE, ROn-1, in the chromosomes of O. niloticus. The ROn-2 element is 359 base pairs (bp) in length, contains short direct terminal repeats, a tRNA-related region similar to tRNA Val and tRNA Arg, a tRNA-unrelated region, and a poly-A tail. Analysis of the chromosomal distribution of ROn-1 and ROn-2 by fluorescent in situ hybridization showed that both SINE sequences are present in all chromosomes of tilapia, and organized in small clusters. The only exception was a large cluster of ROn-1 repeats found in the middle of the long arm of chromosome 1. In view of our data we discuss the hypothesis that the absence of large clusters of SINE sequences and the structural composition of these sequences may explain the absence of base-specific fluorochrome bands in the chromosomes of tilapia.