BIO-1201 Chapter Notes - Chapter 13: Cri Du Chat, Hypotonia, Sickle-Cell Disease
Document Summary
An allele is the result of a mutation. Gene mutation: change in the sequence of the basis of a gene. Gene mutations caused by: transposons specific dna sequences that have the ability to move within and between chromosomes, jumping genes, dna replication rare, an environmental mutagen radiation, pesticides, cigarette smoke. Point mutations (base substitution) change in a single dna nucleotide: results can be minor severe, sickle cell disease. Frameshift mutation caused by an extra or missing nucleotides in a dna sequence: more severe than point mutations, deal with insertions and deletions, tay-sachs, croh(cid:374)"s, prostate ca(cid:374)cer. Chromosomal mutations (including non disjunction: down syndrome, turner syndrome, klinefelter syndrome, changes in chromosome structure are more common, occur during meiosis. Duplication a chromosome segment is repeated so that the individual has more than 2 alleles for certain traits. Inversion means a segment joins in the direction opposite from normal: poor speech skills, seizures, mental disabilities, curved spine, poor muscle tone.
