Section Of Genetics
Welcome to Dr. Simeon Boyd's Lab
Birth defects are the leading cause of infant mortality in the United States, accounting for more than 20% of all infant deaths, yet the causes of about 70% of all birth defects are still unknown. My lab is involved in studies of non-Mendelian (multifactorial) birth defects, such as nonsyndromic craniosynostosis, bladder epispadias-exstrophy complex, and cleft lip and/or palate. Our ultimate goal is to identify genes and environmental factors contributing to the risk of these birth defects. Our initial approach involves recruitment and systematic evaluation of a large group of affected families. This allows for unbiased ascertainment of the clinical and epidemiologic characteristics of these defects and their phenotypic variability. Genome-wide linkage studies have been instrumental in elucidating the etiology of numerous single-gene diseases. For multifactorial traits such as most of the birth defects, these methods have proven less successful. Our strategy is to use case-parent trios with birth defects for SNP based association studies on groups of candidate genes or, more recently, using SNP chips for genome-wide coverage. It is important to emphasize that these approaches can be successfully used for genetic analysis of any complex trait, i.e. autism, diabetes, and hypertension. We are happy to collaborate and provide genetic expertise to clinicians and researchers interested in multifactorial human disorders.
My lab is also involved in identification and characterization of genetic syndromes due to defects of the intracellular secretory pathway. We have recently identified and characterized a new autosomal recessive genetic syndrome, Cranio-Lenticulo-Sutural dysplasia (CLSD; OMIM 607812). This syndrome manifests with early onset cataracts, facial dysmorphisms and late closing fontanels. After mapping CLSD to chromosome 14q13 we identified the causative mutation in SEC23A, an integral member of the COPII complex that transports proteins from the endoplasmic reticulum to the Golgi complex. After characterization of a morpholino zebrafish model we are now working on creating transgenic Sec23a deficient mice. This murine model will allow more detailed analysis of the secretory pathway and its role in health and disease. Using classical and reverse genetic approaches we plan to identify and characterize other human disorders caused by defects of the individual components of the secretory pathway.