the human genome Flashcards
What are the 3 functions DNA has to fulfil?
- encode all info required to make an organism
- must replicate itself accurately
- must allow beneficial mutations to be selected
Define genetics?
the study of heredity, the process by which characteristics are passed from parents to offspring
What is a gene?
a unit of biological information that encodes a specific protein or regulatory molecule
What is precision medicine?
data-driven approach to treating and preventing diseases that considers each person’s unique genes, environment, and lifestyle
Give stats for what makes up our genome?
- 3.2 billion bases of DNA
- 50% high copy repetitive elements
- 1.5% protein coding
- only 20,000 genes
Describe the extent of human genetic variation
- our genes are 99.9% identical
- each have 3 million SNPs
- each have 50-100 SNPs associated with an inherited disease (healthy bc we r diploid)
What is the clinical relevance of genomics in personalised medicine?
- predictive medicine
- pharmacogenetics
- ethics
Describe the structure of DNA?
- double helix of nucleic acid
- complementary strands (AT, CG)
- sequence of bases codes for different proteins
- hydrogen bonds
Describe the first level of DNA folding
- in the nucleosome
- 8 histones (2x H2A, H2B, H3, H4)
- histones +ve charged, DNA -ve
Describe the second level of DNA folding
- requires histone H1 for 30nm fibre
How is DNA condensation regulated?
- chromatin-remodelling complexes
- histone-modifying enzymes (acteyl phosphate/methyl groups)
What are epigenetics?
heritable changes in gene function without changes in base sequence of DNA
What is the clinical relevance of genomics in functional medicine?
- mechanisms of disease
- targeted therapeutics and gene therapy
- human evolution
What is the ENCODE project?
- encyclopaedia of DNA elements
- used sequence analysis and experimental approaches to identify ‘functional’ DNA units
What is RSTS?
- Rubinstein-Taybi syndrome
- mutation in histone acetyl-transferases
