Human Molecular Genetics - Lecture Twenty Two : Why sequence the Human Genome ?
7 important questions on Human Molecular Genetics - Lecture Twenty Two : Why sequence the Human Genome ?
Why is the genome sequenced ?
This allows us to :
- Analyze genetic variation between humans
- Understand diseases (cancer) and treatment options
- Develop new sequencing technique and computational analysis
- Form a database where the genome information can be shared and used for other research by scientists worldwide
- Packaged in 22 autosomes, X and Y chromosomes
- Half from each parent
- In total 6 million base pairs
What are the key findings from the human genome ?
- Nuclear DNA has <21,000 genes, the protein-coding exons (1.5% of genome, much less than expected!)
- Other parts of the genome codes for:
- Unique non-coding DNA
- Repetitive DNA
- - 25% unknown
- The genome is dynamic Human genes are similar to those of other animals
- All humans are 99.9% similar at sequence level
What is SNPs Single nucleotide Polymorphism variation in the Human Genome ?
After sequencing genome of many people, you have a lot of variation data to work with. They can then do Genotyping (analyzing common variants) :
- Causative SNPs: can result in different phenotypes (muscle type) and predilection to diseases a)
- Coding SNP: change amino acid sequence
- LInked SNP: Not all SNPs result a change to the function, not in gene, can be just inherited variations (give information of ancestry)
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
What is InDels Small Insertions or Deletions variation in the Human Genome ?
- Second most common variant in human genome
- If not a 3 nucleotide change, cause frame shift, changing the way a DNA is read
- Cystic fibrosis is caused by CFTR
What is STRs Short tandem Repeat ?
- Repeats of 2-5 nucleotides found in specific regions of genome
- Length Variation can be seen in different alleles (maternal and paternal)
- Used to create genetic profiles called DNA fingerprints
What is the CNV Copy number variations in the Human Genome ?
- Chunks of DNA (500+ bp ) are deleted are duplicated, with reference to a specific genome
- Can be within and between gene
- Many are involved with genes for sensory perception (sight & smell etc) and immunity
Why is variation important in the Human Genome ?
- Variation is heritable and key driver of evolution (thus used to trace ancestry)
- Give rise to different traits that allow for different responses to the environment, contributes to natural selection
- Comparison between variations in gene and the resulting phenotype can give understanding to diseases and treatment
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
![Trustpilot Logo](/images/design_2020/lp/clp-trustpilot-en.png)