Chromosomal Abnormalities - Download as PowerPoint

Document Sample
Chromosomal Abnormalities - Download as PowerPoint Powered By Docstoc
					Chromosomal Abnormalities

   Mutations in multiple genes
             Typical Karyotype
• 22 pairs of
  autosomes
• XX female
• XY male                     QuickTime™ an d a
• Chromosomes        TIFF (Uncompressed) decompressor
                        are need ed to see this p icture .

  different sizes,
  banding
  patterns,
  centromere
  locations
         How to make a karyotype
• Cells are obtained from WBC
• Grow in culture
• Stopped in metaphase
• Cells lysed, spread on slide,
  dried
• Stained and observed

                                           QuickTime™ an d a
                                  TIFF (Uncompressed) decompressor
                                     are need ed to see this picture .
 What happens when something
         goes wrong
• Aneuploidy                      QuickTime™ an d a
                         TIFF (Uncompressed) decompressor


  – Abnormal number of
                            are need ed to see this p icture .




    chromosomes
  – Can bea monosomy
  – Can be a trisomy
                                  QuickTime™ an d a
                         TIFF (Uncompressed) decompressor
                            are need ed to see this p icture .
 How might
   these
aneuploidies            QuickTime™ an d a
               TIFF (Uncompressed) decompressor
                  are need ed to see this p icture.


come about
Nondisjunction



              QuickTime™ and a
    TIFF (Uncompressed) decompressor
       are need ed to see this picture.
       Autosomal Aneuploidy
• Trisomy 21
• Risk factor is age of
  mother
• Physical                         QuickTime™ an d a
                          TIFF (Uncompressed) decompressor
                             are need ed to see this picture.



  characteristics
• Reduced mental
  development
 Other Autosomal Aneuploidies
• Edwards syndrome Trisomy 18
• Pateau Syndrome Trisomy 13

• All infants with these conditions do not
  survive to their first birthday
Are some chromosomes more
prone to nondisjunction than
          others?


                QuickTime™ and a
      TIFF (Un compressed) decompressor
         are neede d to se e this picture.
  Sex Chromosome Abnormalities
• Which chromosome is
  dominant, X or Y
• Turner Syndrome XO               QuickTime™ and a
                          TIFF (Uncompressed) decompressor
                             are need ed to see this picture.



• Klinefelter Syndrome
  XXY
• Triple X Syndrome XXX
• Super Y syndrome XYY

                                    QuickTime™ and a
                          TIFF (Un compressed) decompressor
                             are neede d to se e this picture.
ID the karyotype



          QuickTime™ and a
TIFF (Un compressed) decompressor
   are neede d to se e this picture.
ID the Karyotype



          QuickTime™ and a
TIFF (Un compressed) decompressor
   are neede d to se e this picture.
ID the karyotype



          QuickTime™ and a
TIFF (Un compressed) decompressor
   are neede d to se e this picture.
           Chromosomal Mutations
Can cause extra copies or missing copies of portions of chromosomes

 Remember, chromosomes are goopy




                                   QuickTime™ an d a
                         TIFF (Uncompressed) decompressor
                            are need ed to see this picture.
Specific Kinds of Chromosomal
           Mutations



                 QuickTime™ an d a
       TIFF (Uncompressed) decompressor
          are need ed to see this p icture .
Translocation



         QuickTime™ an d a
TIFF (Uncompressed) decompressor
   are need ed to see this picture.
        3 Kinds of Mutations
• Point / frameshift mutations

• Chromosomal Mutations

• Aneuploidy
    The Ethical Question:
What do you do once you know?


                QuickTime™ an d a
       TIFF (Uncompressed) decompressor
          are need ed to see this picture .




    Syndrome like Down’s
     Male vs Female child

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:77
posted:9/29/2012
language:English
pages:18