|Epigenetics – Turning genes on and off|
The BBC Horizon documentary The ghost in your genes, successfully explains a particularly complex field of science. Genetic inheritance has historically been thought of as involving the transmission of DNA from one generation to the next affected by occasional mutations in the DNA itself (00:04:37 – 00:05:50). “Up to now, inheritance is just the genes, the DNA sequence. I suspect that we’re going to be able to demonstrate that inheritance is more than that”, explains Professor Marcus Pembrey from the Institute of Child Health, UCL. A few scientists had hypothesised that the conventional genetic model and mode of inheritance was too simplistic to explain the complexity of human beings. The revelation that the human genome likely contains only about 30,000 genes (00:08:54 – 00:11:33), coupled with increasing experimental evidence, now leads scientists to believe that other factors allow genes to be switched on and off in response to environmental stimuli. The consequences of which may affect subsequent generations.