Associate Professor
Department of Pediatrics, Genetics, and Investigative Medicine

Our primary research interest is in finding and characterizing genes that cause reading disability, commonly known as dyslexia. Dyslexia is present in 10 to 20% of school children and is the most common cause of learning disability. It is also mostly genetic in origin with genetic factors accounting for 40% to 60% of the poor performance in reading tests. Through genetic studies of families and children with dyslexia we identified a major contributing gene, called doublecortin-domain-containing-2 (DCDC2) (Meng et al, PNAS 102: 17053-17058, 2005). We found that a deletion in a putative regulatory sequence in DCDC2 is present in ~20% of dyslexics. We have now found 20 variations (alleles) of this regulatory (enhancer) sequence and our present studies are focused on identifying which alleles are the most deleterious and which may be protective, and how these variations functionally alter brain development using immunocytochemistry, RNAi, a mouse knockout model, and other molecular approaches in animals. We are also studying how variations of DCDC2 and other dyslexia genes alter brain activation patterns in human subjects using functional magnetic resonance imaging (fMRI), and brain cytoarchitecture using voxel-based morphometry analyses of gray matter and fractional anisotropy.

Current Research:

We are also studying the genetic contributions to common disorders of prematurely born infants. Using heritability analyses of identical and non-identical twins born less than 32 weeks gestational age (before the 7th month of pregnancy), we found that genetic factors account for at least 45% of the variance in liability for a common form of chronic lung disease called bronchopulmondary dysplasia (Bhandari et al, Pediatrics, 117(6):1901-1906, 2006), 70% of the variance for the most common form of blindness called retinopathy of prematurity (Bizzarro et al, Pediatrics, 118(5):1858-1863, 2006), and 70% of the variance for the most common congenital heart disease called patent ductus arteriosus (PDA).

Contact Information:

Email: Jeffrey.Gruen@yale.edu