check it and ask question in comments!

1. GENE LINKAGE
Rida Shinwari
BS Genetics
7th semester
University of swat

2. Gene linkage
 The tendency of genes on closed loci to remain together during
gametes formation is called gene linkage.
 Each chromosome carry many genes o
on it.
 All the genes located on the same
chromosome relinked with each
other

3.  It is the physical relationship between genes.
 A chromosome have blocks of genes termed as linkage group.
 A scientist Morgan explained that genes that do not assort
independently and joined together termed as genetic linkage

4.  Genes whose loci are more nearer to each other are
less likely to be separated into different chromatids
during chromosomal crossing over.
 In other words the nearer the two are on
chromosome the lower is the chance of swap
occurring between them and more likely the are
inherited together.

5. The discovery of genetic linkage
 Two scientist named as William bateson and
Reginald punett determined allele on the same
chromosome passing together.
 They used sweet peas and follow the inheritance
pattern particularly flower color and shape.

6. • For flower color purple was dominant over red.
• Long pollen shape is dominant over round.
• A cross was performed using purple/ long and red/round
• The f1 generation was pure purple and long.

7.  After crossing the f1 generation.
 The offspring appear in f2 with purple long and red round.
 looking to the purple and long showed that the genes
were linked so they didn’t assort (segregate).

8. Types of linkage
• Complete linkage if two or more characters are
inherited together and consistently appear in more then
two generation is called complete linkage.
• these genes do not produce non parental combination.
• And are closely located on same chromosome.

9. Incomplete linkage in complete linkage are exhibited by those
genes which produce some percentage of non parental
combination.
 Such genes are slightly away on loci.
 It is due to accidental of chromosomal segment breakage
during crossing over.

10. Significance of gene linkage
 Linkage reduces the chances of recombination of genes and
hold parental characteristics together.
 Its helps an organism to hold its parental, racial, and other
characters.
 Linkage do not permit the breeder to bring the desirable
in plant in animal it become quite dificult for them.

11. Any question?