Exam 4- Pedigrees and probabilities

Question 1

used to determine the mode of inheritance of genetic traits in humans, and is most useful for relatively rare conditions caused by single genes

Answer 1

pedigree analysis

Question 2

a family tree, drawn using standardized symbols

Answer 2

pedigree

Question 3

pedigree: generations are marked with

Answer 3

roman numerals

Question 4

the individual whose phenotype first brought attention to the pedigree, often the family member who is seeking medical or genetic advice

Answer 4

proband

Question 5

commonly observed patterns of inheritance (3)

Answer 5

• autosomal recessive
• autosomal dominant
• x-linked recessive

Question 6

unaffected parents have affected children

Answer 6

likely recessive

Question 7

males and females affected equally

Answer 7

likely not X-linked

Question 8

father (I-2) carries recessive allele but is not affected

Answer 8

not X-linked

most likely: autosomal recessive

Question 9

autosomal recessive inheritance example:

recessive traits typically

Answer 9

skip generations

Question 10

autosomal recessive inheritance example:

recessive autosomal traits appear

Answer 10

equally in both sexes

Question 11

if the condition is rare in the general population, unrelated mates are

Answer 11

unlikely to be carries

Question 12

autosomal recessive conditions are more likely to appear in ___ unions

Answer 12

consanguineous (shared blood)

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

X-linked recessive

Question 16

Answer 16

X-linked dominant

Question 17

it is possible to encounter ___ ___ when observing real-life pedigrees for some diseases or traits

Answer 17

incomplete penetrance