Sister chromatid exchange and proliferation pattern in lymphocytes from newborns, elderly subjects and in premature aging syndromes

ESCOLA PAULISTA MED SCH,DISCIPLINA GENET,CAIXA POSTAL 20363,BR-04034 São Paulo,BRAZILESCOLA PAULISTA MED SCH,DISCIPLINA GENET,CAIXA POSTAL 20363,BR-04034 São Paulo,BRAZILESCOLA PAULISTA MED SCH,DISCIPLINA GENET,CAIXA POSTAL 20363,BR-04034 São Paulo,BRAZILWeb of Scienc

Unusual duplication in the pericentromeric region of chromosome 9 in a patient with phenotypic alterations

Several alterations involving the pericentromeric region of chromosome 9 are considered as normal population variants. These heterochromatic variants or heteromorphisms can include 9qh+, 9cen+, 9ph+, 9ph-, inv(9)(p11q13), and other patterns which can only be defined by FISH studies. However, some heteromorphisms have been found more frequently in patients with several clinical disorders. Here, we report on a patient with intellectual disability, language and neurodevelopmental delay, as well as facial dysmorphism and an unusual chromosome 9. While the banding karyotype was indicative of a simple pericentric inversion of one chromosome 9 [46, XX, inv(9)(p12q13)], array comparative genomic hybridization showed a 6-Mb duplication, including 22 genes: arr[hg19] 9p13.1p11.2(38,869,901-44,870,714) x3 dn. Molecular cytogenetics using a panel of probes specific for the pericentromeric region of chromosome 9 showed an unusual, rearranged chromosome 9, der(9)(pter -> p11.2Sao Paulo Research Foundation (FAPESP), Brazil [2014/11572-8]Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, BrazilInstitut für Humangenetik, Universitätsklinikum Jena, Jena, GermanyGenetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, Rua Botucatu 740, BR-04023900 Sao Paulo, SP, Brazil.FAPESP: 2014/11572-8Web of Scienc

Enantio- and Diastereoselective Access to Distant Stereocenters Embedded within Tetrahydroxanthenes : Utilizing ortho-Quinone Methides as Reactive Intermediates in Asymmetric Brønsted Acid Catalysis

Background: Complex small supernumerary marker chromosomes (sSMC) constitute one of the smallest subgroups of sSMC in general. Complex sSMC consist of chromosomal material derived from more than one chromosome; the best known representative of this group is the derivative chromosome 22 {der(22)t(11;22)} or Emanuel syndrome. in 2008 we speculated that complex sSMC could be part of an underestimated entity.Results: Here, the overall yet reported 412 complex sSMC are summarized. They constitute 8.4% of all yet in detail characterized sSMC cases. the majority of the complex sSMC is contributed by patients suffering from Emanuel syndrome (82%). Besides there are a der(22)t(8;22)(q24.1;q11.1) and a der(13)t(13;18)(q11;p11.21) or der(21)t(18;21) (p11.21;q11.1) = der(13 or 21)t(13 or 21;18) syndrome. the latter two represent another 2.6% and 2.2% of the complex sSMC-cases, respectively. the large majority of complex sSMC has a centric minute shape and derives from an acrocentric chromosome. Nonetheless, complex sSMC can involve material from each chromosomal origin. Most complex sSMC are inherited form a balanced translocation in one parent and are non-mosaic. Interestingly, there are hot spots for the chromosomal breakpoints involved.Conclusions: Complex sSMC need to be considered in diagnostics, especially in non-mosaic, centric minute shaped sSMC. As yet three complex-sSMC-associated syndromes are identified. As recurrent breakpoints in the complex sSMC were characterized, it is to be expected that more syndromes are identified in this subgroup of sSMC. Overall, complex sSMC emphasize once more the importance of detailed cytogenetic analyses, especially in patients with idiopathic mental retardation