Shwachman-Diamond Syndrome Presenting as Neonatal Ichthyosis.

Shwachman-Diamond syndrome (SDS) is a rare inherited bone marrow failure syndrome characterized by the triad of exocrine pancreatic dysfunction, cytopenia, and skeletal abnormalities. We report a 5-month-old boy with SDS who presented with generalized ichthyosis in the neonatal period that evolved into more eczematous skin eruptions, accompanied by severe failure to thrive. This report highlights the importance of including SDS as a differential diagnosis in patients who present with early ichthyosis, failure-to-thrive, gastrointestinal symptoms and cytopenia.

RETrace: simultaneous retrospective lineage tracing and methylation profiling of single cells.

Retrospective lineage tracing harnesses naturally occurring mutations in cells to elucidate single cell development. Common single-cell phylogenetic fate mapping methods have utilized highly mutable microsatellite loci found within the human genome. Such methods were limited by the introduction of in vitro noise through polymerase slippage inherent in DNA amplification, which we characterized to be approximately 10-100× higher than the in vivo replication mutation rate.

Precise in vivo genome editing via single homology arm donor mediated intron-targeting gene integration for genetic disease correction.

In vivo genome editing represents a powerful strategy for both understanding basic biology and treating inherited diseases. However, it remains a challenge to develop universal and efficient in vivo genome-editing tools for tissues that comprise diverse cell types in either a dividing or non-dividing state. Here, we describe a versatile in vivo gene knock-in methodology that enables the targeting of a broad range of mutations and cell types through the insertion of a minigene at an intron of the target gene locus using an intracellularly linearized single homology arm donor.