genetic disorder associated with meiosis

• down syndrome - trisomy 21

  • extra copy of chromosome 21
  • chromosomes fail to separate properly
• turner syndrome - occurs in females

  • absence of one of the X chromosomes
• klinefelter syndrome - affects males

  • presence of one or more extra X chromosome
• edwards syndrome - trisomy 18

  patau syndrome - trisomy 13

  • presence of an extra copy of chromosomes 18 & 13
• jacob's syndrome - XYY syndrome

  • involves males
  • extra Y chromosome
• cri du chat syndrome - caused by a deletion on the short arm of chromosome 5
• angelman syndrome and prader-willi syndrome

  • deletions or disruptions in the long arm of chromosome 15
• angelman syndrome there is typically a deletion or inactivation of the maternal copy of the chromosome
• prader-willi syndrome, the paternal copy is affected
• fragile X syndrome - caused by an expansion of CGG repeats in the FMRI gene on the X chromosome

  • considered a trinucleotide repeat disorder
• duchenne muscular dystrophy (DMD) and becker muscular dystrophy (BMD) are caused by mutations in the dystrophin gene