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Expected Phenotypes of F2 Cross - One Autosomal Trait and One sex Linked Trait. Complete Dominance. |
The Expected Genotypic and Phenotypic Arrays in the F2 cross for an autosomal gene with complete dominance is :
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Genotypic Array |
Phenotypic Array | |
| Females | 1/4A1A1: 1/2A1A2: 1/4A2A2 | 3/4A1+ 1/4A2 |
| Males | 1/4A1A1: 1/2A1A2: 1/4A2A2 | 3/4A1+ 1/4A2 |
The Expected Genotypic and Phenotypic Arrays in the F2 cross for an X-linked gene (Y chromosome not shown) with complete dominance is :
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Genotypic Arrays and Phenotypic Arrays for Sex-Linked traits in the XY system* |
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| Gen | Genotypic
Array X--linked (female) |
Genotypic
Array Y-linked (male) |
Phenotypic
Array females |
Phenotypic
Array Males |
| F2 | 1/2X1X1:1/2X1X2 | 1/2X1:1/2X2 | 100% X1 | 1/2 X1: 1/2X2 |
| F2' | 1/2X1X2:1/2X2X2 | 1/2X1:1/2X2 | 1/2 X1: 1/2X2 | 1/2X1: 1/2X2 |
| F2 '' | 1/2X1X2:1/2X2X2 | 1/2X1:1/2X2 | 1/2 X1: 1/2X2 | 1/2X1: 1/2X2 |
| F2 ''' | 1/2X1X1:1/2X1X2 | 1/2X1:1/2X2 | 100% X1 | 1/2X1: 1/2X2 |
*There are different arrays for males and females for each of the four F2 crosses
The joint phenotypic array for an autosomal gene and an X-linked gene is obtained by multiplying the separate phenotypic arrays.
Example : In the F2 generation the expected phenotypic arrays are:
Females: (3/4A1+ 1/4A2) * (X1) = 3/4A1X1+ 1/4A2X1
Males: (3/4A1+ 1/4A2) * (1/2X1:1/2X2) = 3/8A1X1 + 3/8A1X2 + 1/8A2X1 + 1/8A1X1
As long as you can develop a phenotypic array for any single gene, the joint phenotypic arrays for 1, 2 , 3 etc genes can be derived by multiplying the separate phenotypic arrays:
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Quick Links F2 Cross |
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| 1 | Basic F2 cross - autosomal genes |
| 2 | Basic F2 cross- X-linked gene |
| Expected Phenotypes of F2 Cross - Single Autosomal Traits | |
| Expected Phenotypes of F2 Cross - X-linked gene | |
| 4 | F2 cross - two unlinked autosomal genes |
| 5 | F2 cross - one autosomal - one X-linked gene |
| 6 | Linkage - Coupling and Repulsion |
| 7 | F2 cross - two linked autosomal genes -coupling |
| 8 | F2 cross - two linked autosomal genes - repulsion |
| 9 | Measuring the recombination rate from F2 data |
| Recombination from F2 data - Table of Values | |
| 10 | Basic F2 cross- Z-linked gene (inactive) |
| 12 | Expected Phenotypes of F2 Cross - Z-linked gene (inactive) |
| 13 | F2 cross - one autosomal - one Z-linked gene (inactive) |
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Also See |
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| Detection of Linkage - Basic Info - Two Autosomal Traits - Complete Dominance | |
| Detection of Linkage - More complex examples | |
| Detection of Linkage - One More Example | |
| Detection of Linkage - Two Autosomal Traits - Heterozygote has Unique Phenotype | |
| Home page | |
| Detailed List for Mendelian Genetics | |