GH GLS 4 - pedigrees

Female

Male

Affected Female

Affected Male

Sex unknown

Pregnant (with a child of unkown sex)

Marriage or Defacto

Offspring (siblings)

Bottom row

miscarriage (spontaneous abortion)

identical (monozygotic) twins

Non - Identical (Dizygotic Twins)

relationship ceased

Second marriage

consanguineous relationship

dead female/male

stillbirth

terminated pregnancy (shade if abnormal)

female carrier for x-linked

adoption

Identical twins (alternative)

fraternal twins (dizygotic twins - alternative)

proband - person who prompted pedigree analysis

Individuals in every generation are affected

What is a vertical pattern?

individuals in one generation are affected (skips generations)

What is a horizontal pattern?

I-2 may be a carrier,

II-1 may be a carrier,

II-3 may be a carrier

This looks like it may be a dominant trait. How could it also be recessive?

1/3 (2/3 chance Taneesha is a carrier x 1/2 chance she passes the affected alelle on)

(We assume that her partner is not affected)

What are the chances Taneesha's child may inherited the affected allele?

1: look for the chances for the genotype for each trait.

2: multiply the likelihood for each genotype together

When looking at likelihood for certain genotypes in offspring, how does the product rule determine this?