Analyzing the relationship between disease and development

Some hereditary diseases are characterized by developmental defects in specific organs and tissues, yet their molecular basis often remains unclear. Recently, RNA-sequencing data collected from seven organs (brain, cerebellum, heart, kidney, liver, testis and ovary) across developmental stages from early pregnancy through birth became available. We used these data to analyze the relationships between hundreds of organ-specific developmental and disease-causing genes. We found a significant overlap between the two types of genes in their respective organ, across all organs, showing the tight connection between disease and development. Moreover, the expression pattern of both types of genes was highly variable during development of their associated organ. We also found that the co-expression pattern of paralogous genes during organ development was associated with the manifestation of a disease in that organ. Such analyses may explain why certain mutations cause severe defects in specific organs while other organs expressing the same causal genes remain unaffected.