Application of genome and exome sequencing to study craniofacial conditions–A primer

With the development of Sanger DNA Sequencing in the 1970’s, the scientific community gained a new tool to understand relationships between phenotype and genotype. This methodology allowed one to sequence small regions of DNA in the human genome, but was expensive, time consuming and used radioactive labels; making it impractical to use to study an entire human genome. As technologies improved, DNA amplification by polymerase chain reaction (PCR) in the 1980’s allowed scientists to selectively amplify a targeted DNA sequence. This advancement, along with the utilization of fluorescently–labeled nucleotides significantly influenced the automation of sequencing technology. Today, Next–Generation Sequencing (NGS) can affordably sequence millions of DNA fragments simultaneously and is being used to examine the entire code of the human genome. This capability is revolutionary and offers new hope in identifying key genes involved in numerous craniofacial anomalies.