L & S C30Y Lecture Notes - Lecture 8: Microglia, Smooth Muscle Tissue, Osteoblast
Document Summary
Methylation methyl groups can be attached, it"s a way of controlling transcription. If base pairs are methylated so they don"t get transcripted: makes them not be readable. It could have the same gene, but if one is methylated it"ll be expressed differently. Dna methylation creates heritable marks on dna. Mosaics and balancing sex chromosome gene dosage. Inherited differences without a difference in underlying dna. The difference in the behavior of chromosomes that is impressed upon them in the preceding generation by the sex of the parent. Differentiation of many cell types from the fertilized egg is an example of epigenetic inheritance. Missing entirely from s. pombe, s. crevisiae, c. elegans, drosophila. Present in plants, mammals, neurospora, and bacteria. Methyl cytosine changes the structure of the major grove of dna. Key point: unbalanced gene dosage leads to problems mental deficiency in humans.