or so sayeth John Donne, a Jacobean poet and preacher.  I'm sure I am not original in my view that what Donne was speaking of with this phrase: most certainly the concept that no person is independent of the influence of others or the influence that they may have on others.

 The same could be said of genes.  Genes are not found floating in the nucleus of cells as independent entities.  Nay, they are found as part of chromosomes, 46 of which are found in the nucleus of most cells in our body.  Each chromosome is composed of two strands of DNA winding about one another, one heading left to right and the other right to left (so to speak).  These strands of DNA are composed of deoxyribonucleotides linked to one another through phosphodiester bonds.  There are millions, sometimes hundreds of millions, of deoxyribonucleotide units per strand of DNA in each of our chromosomes.

 Within these hundreds of millions of deoxyribonucleotide units is information that codes for the tens of thousands of proteins residing in the human genome.  This information is stored within the sequence of the four-deoxyribonucleotide bases that make up DNA (GATC).  As has been discussed in this forum previously, each of these genes contains additional information (also embodied in the base sequence) needed for the appropriate expression of each gene.  By appropriate, I mean that the gene is expressed in the correct cell type, at a fitting time in development, and in just the right amounts.

 When one cell becomes two during cell division, all this genetic information spread across 3.5 billion base pairs of DNA needs to be faithfully copied with one genetic blueprint retained in the original mother cell and the second transmitted to the newly created daughter cell.  This segregation of genetic information between mother and daughter cell is made much easier by having our genes packaged in 46 chromosomes as opposed to having to distribute exact copies of tens of thousands of individual genes between mother and daughter cells during each cell division.

 These requisites for faithful transmission of genetic information from one cell to another bring us to this month's Journal Club.  The manuscript I'll be discussing is from the laboratory of Stefan Karlsson, an established investigator in the DBA field who has had a longstanding interest in using gene therapy as a cure for DBA.  The title of the article is "Gene therapy cures the anemia and lethal bone marrow failure in a mouse model for RPS19-deficient Diamond Blackfan anemia"1.