October 30, 2021.

Our Multiplex PCR Assay for Identifying All Major SARS-CoV-2 Variants has been uploaded to medRxiv.  This is a two tube assay that effectively and accurately detects currently circulating Covid-19 variants in less than three hours from RNA extracted from patient samples.  Procedures to rapidly develop similar tests for variants of concern that will emerge in future are described.

October 10, 2021. 

Stop the noise emanating from the genes. In a paper just published in Proceedings of the National Academy of Sciences, we explored the molecular origins of the enigmatic phenomenon of “noise” in gene expression. We show that mammalian genes are not expressed in a steady and continuous stream but are expressed in episodic bursts. This occurs because the regulatory regions of genes are normally hidden in impervious chromatin and random “breathing” events in chromatin provide intermittent access to factors that turn the genes on, rendering the gene expression intermittent. The picture of human cell on the right shows nuclei in blue, certain active genes in orange, and their mRNA products in red.


June 20, 2019. 
Our article on amplified FISH is published  in the
Proceedings of the National Academy of Sciences.

This paper describes a method that produces amplified signals from single RNA molecules, using Hybridization Chain Reaction and probes in which the HCR initiator sequence is conditionally sequestered.  The binding of probes to a target unmasks the initiator and generates an amplified signal. These probes enable detection of sparsely expressed mRNAs and are so specific that related mutant and wild-type mRNAs, differing from each other by as little as a single-nucleotide variation, yield distinct in situ signals in two distinguishable colors.  This technology will aid in studies of differential expression from alleles and will be useful for the identification of mRNAs harboring somatic mutations in cancer tissue biopsies.


April 12, 2019. 

LaTasha Fraser successfully defends her Ph.D. dissertation, "Exploring the Role of Chromatin Decondensation at a Gene Locus in Stochastic Gene Expression".


November 1, 2018. 

Arjun Raj and Sanjay Tyagi receive Thomas Alva Edison award for their patent on single-molecule FISH (Stellaris) probes.

Edison-Statue-by-Nico Gold-Vargas.jpeg