1. Gene Linkage and Mapping

2. Remember Mendel’s Laws
Law of Segregation
Alleles for a trait will separate independently from each other during gamete formation
Law of Independent Assortment
Homologous chromosomes will separate independently from other homologous chromosomes

3. Linked Genes A1, B1 & C1 are linked genes

4. Crossing over can UNLINK genes!
Recombinants

5. higher rate of crossing over Genes further apart
Less likely to be linked = =
Linked
Not linked

6. Purple (R) is dominant over red (r)
RRLL x rrll
Purple (R) is dominant over red (r)
Long pollen (L) is dominant over round pollen (l)
RrLl

7. RrLl

8. RrLl
The law of independent assortment does not always apply with linked genes