1. Karyotypes Objective: E6 - Describe how techniques such as chromosomal analysis (karyotypes) are used to study the genome of organisms

2. Karyotypes Sex ChromosomesAutosomes Human Female Karyotype AutosomesSex Chromosomes Notation: 46,XY46,XX Diagnosis: Normal male Diagnosis: Normal female

3. Analyzing Karyotypes A karyotype displays a diploid number of chromosomes.

4. Chromosomal disorders Nondisjunction – means “not coming apart”; - when homologous chromosomes fail to separate, abnormal chromosome numbers may find their way into gametes

5. Monosomy – missing one chromosome from a pair Exp. Monosomy 23 – missing a sex chromosome Notation: 45,X0 Trisomy – having three copies of a chromosome Exp. Trisomy 18 – extra chromosome 18 Notation: 47,XX,+18 or 47,XY,+18

6. Does this person have a normal # of chromosomes? What was it caused by? Is this person a male or a female? What notation would you use to characterize this patient’s karyotype? What condition does this person have? male Trisomy 21 (Down Syndrome) Nondisjunction 47, XY, +21 No

7. Common Non-disjunction Disorders Turner’s Syndrome – Monosomy 23 Notation: 45,X0 Kleinfelter’s Syndrome – Trisomy 23 Notation: 47,XXY Down’s Syndrome – Trisomy 21 Notation: 47,XX,+21 or 47,XY,+21 Edward’s Syndrome – Trisomy 18 Notation: 47,XX,+18 or 47,XY,+18 Patau Syndrome – Trisomy 13 Notation: 47,XX,+13 or 47,XY,+13

8. Amniocentesis Amniotic fluid withdrawn - a procedure a pregnant woman can have in order to detect some genetics disorders…such as non-disjunction.

9. How are Karyotypes made?

10. Practice: What is the sex of this patient? What notation would you give this patient? What diagnosis would you give this patient? Female (Why? No Y chromosome) 45, XO Monosomy 23

11. Now, you are going to pretend to be a geneticist and diagnose patients by looking at karyotypes. Karyotype Activity Due Today