Pedigrees

Using Pedigrees Humans cannot be selectively bred like Mendel’s pea plants Geneticists use pedigrees to: Study human genetic disorders Predict the probability that a person has or carries a specific trait

Pedigree Symbols male female mating (square on left) children (birth order left to right)

Pedigree Symbols carrier (has a recessive gene for the trait) non-affected (does not have trait) carrier (has a recessive gene for the trait) affected (has the trait)

Pedigree Symbols I II III Each generation is labeled with a roman numeral Individuals are labeled from left to right starting with 1 I II III 1 2 3 5 6 7 4 9 8 10 11 12 13 14

Typical Pedigree Types autosomal dominant autosomal recessive sex linked recessive sex linked dominant Mitochondrial inheritance

Autosomal Dominant easiest patterns to recognize one parent affected ½ or all of the children affected will usually have at least one affected in each generation Heterozygous for the trait Homozygous for the trait

Autosomal Recessive Both parents appear to be non-affected but can produce affected children Affected children are homozygous recessive Parents can be shown two ways

X Linked Recessive The father is affected (has the trait) His daughters can be carriers for the trait Only the sons express the trait

X Linked Dominant The father is affected (has the trait) All of his daughters are affected (have the trait) None of the sons express the trait

Mitochondrial Inheritance All of the children of an affected female are affected (have the trait) None of the children of an affected male will have the trait

Russian Royal Families Prince Albert Queen Victoria

Russian Royal Families Instead of numbering them traditionally, start at the top left with #1 and work your way across and then down Number all of the individuals in the pedigree chart.

Russian Royal Families Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

Which numbers are the children of 7 and 8? Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

Color all hemophilia carriers blue Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31 What do all the carriers have in common?

Color all hemophiliacs red Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31 What do the affected have in common?

What relation is number 22 to Queen Victoria? Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31 Do you think Alexis has hemophilia?

Color all non-affected individuals yellow Prince Albert________ Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

Complete the assignment by circling the right answer choice then label individuals mentioned in the story. Turn in to the tray when finished