Lecture 10 - Pedigree Analysis I

Question 1

Why do traits in humans not follow the Mendelian inheritance pattern?

Answer 1

because there is usually more than one gene coding for a trait

Question 2

what are some traits that are governed by one gene and are abnormal, threatening or debilitating?

Answer 2

• Huntington’s disease (dominant allele)
• cystic fibrosis (recessive allele)

Question 3

Why is determining the pattern of transmission in humans more diffifuclt?

Answer 3

1. no pure-breeding lines
2. no controlled matings
3. generation time is long
4. progeny # are small

Question 4

pedigree

Answer 4

pictural representation of a family history

Question 5

proband

Answer 5

person from whom the pedigree is initiated (oldest relative on chart)

Question 6

what are the four modes of inheritance?

Answer 6

• autosomal dominant
• autosomal recessive
• X linked
• Y linked

Question 7

autosome (autosomal)

Answer 7

non-sex chromosomes, anything but X and Y alleles