Laryngeal cleft type IV: One pathology, two different presentations.

Laryngotracheoesophageal cleft is a rare congenital malformation where a communication exists between the aero-digestive tracts that is associated with high morbidity and mortality. In this case series, we describe our experience with two neonates evaluated in our institution with two diverse initial presentations and symptomatology of type IV laryngotracheoesophageal clefts. One patient presented with acute distress and respiratory failure due to bowel contents obstructing the trachea and the other presented with mild subcostal retractions and inspiratory stridor without overt respiratory failure.

Drosophila muller f elements maintain a distinct set of genomic properties over 40 million years of evolution.

The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D.