Genetics Study Guide Ch 2-4
CHAPTER 2: CELLS
Learning about disease is often simplified by growing it in a dish – some cells like heart and nerve cells however do not grow easily outside the body.
Cellular reprogramming takes cell back to a state similar to stem cells and then coaxes them to specialize in a different way.
Example – LEOPARD syndrome MIM 151100. Acronym for symptoms: enlarged heart w/blocked valves to the lungs, freckles, abnormal genitals, deafness. Skin cells taken from patients were reprogrammed to give rise to almost any cell type (with a gene cocktail). Another cocktail stimulated their differentiation – sure enough the muscle cells were too big with rigid filaments and a different set of genes being expressed. Diseased cells then were tuned into a different set of signals than healthy cells.
2.1 Introducing Cells
Understanding cell function in healthy cells allows us to understand what goes wrong in certain cells that suggest treatment. We learn what must be repaired or replaced.
EX: Genes tell cells how to make the proteins that align to form the contractile apparatus of muscles. In Duschenne muscular dystrophy MIM 310200 – one type on muscle protein is missing, and muscle cells collapse under forceful contraction, some become very weak in early childhood. Figure – boy with overdeveloped calf muscles – identifying the missing protein helps, but the number of muscle cells to be corrected causes great difficulty.
Our bodies contain more than 260 specialized or differentiated cell types. Bone, nerve and muscle and subtypes of those. Somatic cells – body cells that have two copies of the genome and called diploid.
Sperm and egg cells – sex cells that have one copy of the genome and called haploid. The meeting of sperm and egg cells restores them to a diploid state.
Stem cells – diploid cells that give rise to differentiated cells and replicate themselves in a process called self-renewal. Stem cells enable the body to develop and grow and repair damage.
Learning about disease is often simplified by growing it in a dish – some cells like heart and nerve cells however do not grow easily outside the body.
Cellular reprogramming takes cell back to a state similar to stem cells and then coaxes them to specialize in a different way.
Example – LEOPARD syndrome MIM 151100. Acronym for symptoms: enlarged heart w/blocked valves to the lungs, freckles, abnormal genitals, deafness. Skin cells taken from patients were reprogrammed to give rise to almost any cell type (with a gene cocktail). Another cocktail stimulated their differentiation – sure enough the muscle cells were too big with rigid filaments and a different set of genes being expressed. Diseased cells then were tuned into a different set of signals than healthy cells.
2.1 Introducing Cells
Understanding cell function in healthy cells allows us to understand what goes wrong in certain cells that suggest treatment. We learn what must be repaired or replaced.
EX: Genes tell cells how to make the proteins that align to form the contractile apparatus of muscles. In Duschenne muscular dystrophy MIM 310200 – one type on muscle protein is missing, and muscle cells collapse under forceful contraction, some become very weak in early childhood. Figure – boy with overdeveloped calf muscles – identifying the missing protein helps, but the number of muscle cells to be corrected causes great difficulty.
Our bodies contain more than 260 specialized or differentiated cell types. Bone, nerve and muscle and subtypes of those. Somatic cells – body cells that have two copies of the genome and called diploid.
Sperm and egg cells – sex cells that have one copy of the genome and called haploid. The meeting of sperm and egg cells restores them to a diploid state.
Stem cells – diploid cells that give rise to differentiated cells and replicate themselves in a process called self-renewal. Stem cells enable the body to develop and grow and repair damage.