1. 27.3 Genetic Disorders Errors in the chromosome number
Genetic Disorders and sex chromosomes
Genetic Disorders and autosomes
Genetic Counseling

2. Errors in Chromosome Numbers
Less than 46 chromosomes OR
More than 46 chromosomes
Due to mistakes in meiosis
Anaphase, chromosomes do not get pulled appart

3. Errors due to Meiosis 4 Possible Gametes Sperm or Egg
*Normal *Normal *Too many *Too few

5. Trisomy Inheriting three copies of a chromosome instead of two
Too many
47 chromosomes

7. Down syndrome Outwardly slanted eyes
Exaggerated fold of skin on the inside of the eye
Flat ears set low on the head
Flattened face
Small teeth
Relatively short arms and legs.

10. Edward syndrome
Defects of the kidneys, ureters, heart, lungs and diaphragm.
Cleft lip or cleft palate.
Small skull (microcephaly).
Malformations of the hands and feet
Neural tube defect, where the spinal cord, meninges and blood vessels protrude through a gap in the vertebrae
Malformations of the sex organs

12. Patau syndrome Small skull (microcephaly).
An abnormal opening in the skull.
Malformations of part of the brain.
Structural defects of the eyes.
Cleft lip or cleft palate.
Additional toes or fingers
Congenital heart disorders, such as ventricular septal defect.
Neural tube defect, where the spinal cord, meninges and blood vessels protrude through a gap in the vertebrae
Malformations of the sex organs.

14. Monosomy Inherit one copy of a chromosome instead of two Too few
45 chromosomes

15. Monosomy Disorders
Turner Syndrome

16. Turner Syndrome condition in females (XX)
Due to an absent X-chromosome
short stature
sexual underdevelopment
physical abnormalities

18. Types of Chromosomes
Autosome: a non-sex chromosomes pairs on a karyotype
Sex chromosomes: the XX or XY pair 23 on a karyotype

20. Genetic Disorders Carried by Sex Chromosomes: Hemophilia
Carried by Autosomes
Dyslexia
PKU

21. Hemophilia
Disorder
Blood can not form clots
Found on recessive gene

23. Dyslexia A learning disorder Can not see or write letters and or words
Appear backwards
Dominant gene

24. PKU
Body lacks the enzyme necessary to metabolize phenylalanine to tyrosine.
Causes brain damage and progressive mental retardation

26. Genetic Counseling
Provide information and support to families who have members with birth defects or genetic disorders Or
to families at risk for a variety of inherited conditions.

27. Counselors
They identify families at risk, investigate the problem present in the family, interpret information about the disorder, analyze inheritance patterns and risks of recurrence, and review available options with the family.

29. Pedigree
a diagram of family relationships that uses symbols to represent people and lines to represent genetic relationships.
Determine the mode of inheritance (dominant, recessive, etc.) of genetic diseases.

30. Pedigree
A series of symbols are used to represent different aspects of a pedigree.

31. Pedigree Dominant traits: Never skips a generation
Two affected individuals can give rise to unaffected individuals
Recessive traits:
may skip a generation
two unaffected individuals can give rise to affected individuals

32. Marriage Line I II
III IV
Children line
Siblings