Decoding the Human Genome
Keywords:comparative genomic hybridization, DNA, fluorescence in situ hybridization, high-throughput nucleotide sequencing, karyotype, multiplex polymerase chain reaction, polymerase chain reaction, sequence analysis
The neonatologist is often the first clinician to identify genetic disorders without prenatal diagnosis. Technological advances in genetics over the past few decades have opened up possibilities never before imagined. Gone are the days when we could offer our patients little more than a peripheral blood karyotype. Newer methods, such as comparative genomic hybridization or Sanger sequencing and next-generation sequencing, allow a more detailed analysis of the human genome, both at the level of large rearrangements (deletions, duplications) and potentially pathogenic point variants. High-tech technologies have been useful in uncovering genes involved in diseases that have long been known to have a genetic origin, but whose etiology has remained elusive. Despite the promise of these technologies, no method is self-sufficient, and all have limitations. The aim of this review is to update clinicians on the genetic tests that are currently available and in use. Given that the first human genome was sequenced just over twenty years ago, what news will the next twenty years bring?
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