Saharan

The internal coherence of the Saharan languages (as a branch of Nilo-Saharan) is undoubted. Several common features of lexicon and grammar are attributed to the common genetic property of the family. It is likewise evident that the Saharan languages in their current form also share features with other languages of the contact area. This especially applies to the syntax of complex sentences. It can be assumed that contact features were adopted when the Saharan languages had separated into independent languages and formed individual categories through direct borrowing or calque processes. In addition, the elaboration of the TAM system also appears to be a result of contact. This chapter highlights major common genetic features, such as pronominal forms and verbal structure, but also points to traces of contact-induced change.

Meiotic recombination is suppressed near the histone-defined border of euchromatin and heterochromatin on chromosome 2L of Drosophila melanogaster

In Drosophila melanogaster, the borders between pericentric heterochromatin and euchromatin on the major chromosome arms have been defined in various ways, including chromatin-specific histone modifications, the binding patterns of heterochromatin-enriched chromosomal proteins, and various cytogenetic techniques. Elucidation of the genetic properties that independently define the different chromatin states associated with heterochromatin and euchromatin should help refine the boundary. Since meiotic recombination is present in euchromatin, but absent in heterochromatin, it constitutes a key genetic property that can be observed transitioning between chromatin states. Using P element insertion lines marked with a su(Hw) insulated mini-white gene, meiotic recombination was found to transition in a region consistent with the H3K9me2 transition observed in ovaries.