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How to write parents genotypes

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Mendelian inheritance

What letters should be used to write parental genotypes?
How correctly mark dominant and recessive alleles in the parental genotypes?
How the program determines which letter represents the dominant allele and which - recessive?
Is it possible to mark allele with multiple letters?
How to mark multiple alleles in the program?
Is it possible to mark the phenotype of wild-type using natural genetic notation - "+" sign?
Is it possible to mark alleles with multiple letters, and use "+" sign to mark the wild-type alleles at the same time?
How to mark traits, that dominate over the "<+>"?

Genetic linkage and X-Linkage

How to mark in the program linked genes?
How to mark in the program X-linked genes?
Is it necessary to mark the chromosome with which the genes are linked only as X or Y?
Is it possible to mark linked genes with multiple letters, and use "+" sign to mark the wild-type allele?
How to write correctly the parental genotypes, if between the linked genes occurs crossing-over (genetic recombination)?
For what number of genes in a linkage group we can use the recombination frequency in the notation of parental genotypes?
Is it possible to mark linked genes with multiple letters, and use "+" sign to mark the wild-type allele for crossing-over genetic problems?

Polygenic inheritance

How to mark in the program polygenes?

Polyploidy and nondisjunction of chromosomes

How to get all possible combinations of gametes for diploids and polyploids, including those that are the result of nondisjunction of chromosomes?
Will the obtained ratio of gametes is valid, if we take into account all possible combinations of gametes?
How to select only normal gametes in polyploids from all possible combinations?
How the program determines which gametes in polyploids is normal?
How to select the gametes with specific ploidy?
Will the obtained ratio of gametes is valid, if we take into account only normal gametes?
Can I use the dominant and recessive notations of alleles for polyploids?
For example, what may be possible parental genotypes of polyploids?
Is it important the order of writing of dominant and recessive alleles for polyploids?
Is it possible to mark alleles for polyploids with multiple letters?

Answers

Mendelian inheritance

Q: What letters should be used to write parental genotypes?
A: For a correct writing of parental genotypes you should use only english letters. For now you can't use letters of another national alphabets. Since the program can only work with the english alphabet. [Back to the top]

Q: How correctly mark dominant and recessive alleles in the parental genotypes?
A:You can use the same letter to mark dominant and recessive alleles, for example, you can mark dominant allele as "A", and recessive allele as "a". But it is not required and you can mark them with different letters, for example, you can mark dominant allele as "R", and recessive allele as "w". [Back to the top]

Q: How the program determines which letter represents the dominant allele and which - recessive?
A: To do that the program use the ascii table. The letter, which are placed higher in order will be dominate over letters, which are placed below. For example "B" will dominate over "G", and "c" over "t". The letters in uppercase dominate over letters in lowercase. Therefore, in order to avoid confusion is preferable to use uppercase letter as the first letter of the dominant allele and a lowercase letter as the first letter of the recessive allele. For example like this:

Example1 : Aa X Aa (monohybrid cross)
Example2 : AaBb X AaBb (dihybrid cross)
Example3 : AaBbCc X AaBbCc (polihybrid cross)
[Back to the top]

Q: Is it possible to mark allele with multiple letters?
A: Yes. There are several ways. In the program you can see the field "Letters in allel". By default this value is 1. You can change this value, for example on 2. And then you can mark the allele with two letters.For example like this:

Example1 : Cscs X Cscs (monohybrid cross)
Example2 : TrtrCscs X TrtrCscs (dihybrid cross)
Example3 : TrtrCscsYwyw X TrtrCscsYwyw (polihybrid cross)

But as you can see, this way have a significant limitation - you must mark all alleles in the parental genotypes by two letters. It's not comfortable. Moreover, we often need to mark alleles with different number of letters. So, there is an easier way to do it. You can use natural notation for the alleles. To do this, you need conclude allele entry in these characters . For example like this:

Example1 : <Yellow><green> X <Yellow><green> (monohybrid cross)
Example2 : <Yellow><green><Big><smoll> X <Yellow><green><Big><smoll> (dihybrid cross)
Example3 : <Yellow><green><Big><smoll><Normal><bar> X <Yellow><green><Big><smoll><Normal><bar> (polihybrid cross)
[Back to the top]

Q: How to mark multiple alleles in the program?
A: The name of the group of multiple alleles marked by one letter, and the identifier concluded in the special characters - X. Parental genotypes should look like this:

Example1 : I<A>I<o> X I<B>I<o>
Example2 : R<Green>R<Yellow> X R<Blue>R<Red>
Example3 : N<A>N<ar> X N<A>N<ar>
[Back to the top]

Q: Is it possible to mark the phenotype of wild-type using natural genetic notation - "+" sign?
A: Yes. You can use the "+" sign to mark the dominant alleles of the wild type. For example like this:

Example1 : +a X +a (monohybrid cross)
Example2 : +a+b X +a+b (dihybrid cross)
Example3 : +a+b+c X +a+b+c (polihybrid cross)
[Back to the top]

Q: Is it possible to mark alleles with multiple letters, and use "+" sign to mark the wild-type alleles at the same time?
A: Yes. The alleles, which are marked by "+", you need just conclude in the special characters - <+>. For example like this:

Example1 : <+><green> X <+><green> (monohybrid cross)
Example2 : <+><green><+><smoll> X <+><green><+><smoll> (dihybrid cross)
Example3 : <+><green><+><smoll><+><bar> X <+><green><+><smoll><+><bar> (polihybrid cross)
[Back to the top]

Q: How to mark traits, that dominate over the "<+>"?
A: This can be done only for the alleles, which are marked with multiple letters. The name of this allele must begin with the character, which are placed higher than the "+" symbol in the table ascii. For example, with "#" character. You can also use for this multiple alleles.

Example1 : <#Yellow><+> X <+><green>
Example2 : A<vy>a<> X I<+>a<>

[Back to the top]

Genetic linkage and X-Linkage

Q: How to mark in the program linked genes?
A: To marking the genetic linkage in the program, you should conclude linked alleles in round brackets - "( )". Each group of linked genes should include two groups of alleles, which are enclosed in parentheses and the number of alleles in these two groups should be the same. The parental genotypes should look like this:

Example1 : (AB)(ab) X (Ab)(aB)
Example2 : (AbC)(aBc) X (ABC)(abc)
Example3 : (ABcD)(aBCd) X (AbCD)(abcd)
[Back to the top]

Q: How to mark in the program X-linked genes?
A: Each group of linked genes is composed of two groups of alleles, which are enclosed in round brackets, so you can simply write the name of the chromosome X or Y before a group of alleles. And in order to demonstrate the lack of genes in the Y - chromosome you must use the symbols "-" or "_" - for each lacking gene. The parental genotypes should look like this:

Example1 : X(AB)X(ab) X X(AB)Y(--)
Example2 : X(ABC)X(abc) X X(ABC)Y(---)
Example3 : X(ABCD)X(abcd) X X(ABCD)Y(----)
[Back to the top]

Q: Is it necessary to mark the chromosome with which the genes are linked only as X or Y?
A: No, it's not necessary. For example you can write parents genotypes like this:

Example1 : R(ABC)R(abc) X R(ABC)R(abc)
Example2 : R(ABC)R(abc) X R(ABC)O(---)
[Back to the top]

Q: Is it possible to mark linked genes with multiple letters, and use "+" sign to mark the wild-type allele?
A: Yes, for example like this:

Example1 : (<Yellow><Big>)(<green><smoll>) X (<Yellow><Big>)(<green><smoll>)
Example2 : (<Yellow><Big><Met>)(<green><smoll><met>) X (<Yellow><Big><Met>)(<green><smoll><met>)
Example3 : (<+><+><+>)(<green><smoll><met>) X (<+><+><+>)(<green><smoll><met>)
[Back to the top]

Q: How to write correctly the parental genotypes, if between the linked genes occurs crossing-over (genetic recombination)?
A: In this case, we must include in the parental genotype entry the valuve of recombination frequency between genes - this value must be concluded in percent symbols (and the value must not exceed 50%). There are three variants for this. Each group of linked genes is composed of two groups of alleles, which are enclosed in round brackets, therefore, the recombination frequency can be included in the notation of any of the groups of alleles, or simultaneously in both. All three variants are correct and you can use the one you like more ( In the last variant you can write different values of recombination frequency, but in this case, the program will be used to solve the problem - only the first value ). For example like this:

Variant1 : (A%20%B)(ab)
Variant2 : (AB)(a%20%b)
Variant3 : (A%20%B)(a%20%b)

Example1 : (A%20%b)(aB) X (Ab)(a%20%B)
Example2 : (+%20%b)(a+) X (+%20%b)(a%20%+)

For X - linked genes:
Example1 : X(A%20%b)X(aB) X X(Ab)Y(--)
[Back to the top]

Q: For what number of genes in a linkage group we can use the recombination frequency in the notation of parental genotypes?
A:You can use the recombination frequency - maximum for the three alleles in each group of linked genes. The values of recombination frequencies for the two parental genotypes may be different, but the sum of these values ??for each of them must not be greater than 50%. For example you can write parents genotypes like this:

Example1 : (A%20%B%10%C)(abc) X (A%20%B%10%C)(abc)
Example2 : (A%20%B%10%C)(abc) X (A%8.4%B%12.5%C)(abc)
Example3 : (A%20%B%10%C)(abc) X (ABC)(a%8.4%b%12.5%c)

For X - linked genes:
Example1 : X(A%20%B%10%C)X(abc) X X(A%26.2%B%16.8%C)Y(---)
Example2 : R(A%20%B%10%C)R(abc) X R(A%20%B%10%C)R(abc)
[Back to the top]

Q: Is it possible to mark linked genes with multiple letters, and use "+" sign to mark the wild-type allele for crossing-over genetic problems?
A: Yes, for example like this:

Example1 : (<Yellow>%20%<Big>)(<green><smoll>) X (<Yellow>%8.4%<Big>)(<green><smoll>)
Example2 : (<Yellow>%20%<Big>%10%<Met>)(<green><smoll><met>) X (<Yellow>%8.4%<Big>%12.5%<Met>)(<green><smoll><met>)
Example3 : (<+><+><+>)(<green>%20%<smoll>%10%<met>) X (<+><+><+>)(<green><smoll><met>)

For X - linked genes:
Example1 : W(<Yellow>%20%<Big>)W(<green><smoll>) X W(<Yellow>%10.6%<Big>)o(--)
Example2 : X(<Yellow>%20%<Big>%10%<Met>)X(<green><smoll><met>) X X(<Yellow>%10.6%<Big>%34.8%<Met>)Y(---)
Example3 : X(<+><+><+>)X(<green>%20%<smoll>%10%<met>) X X(<+><+><+>)Y(---)
[Back to the top]

Polygenic inheritance

Q: How to mark in the program polygenes?
A: If the dominant and recessive alleles of polygenes you mark with the same letters, but in a different register ( dominant - in the uppercase and the recessive in the lowercase ), then starting with version 3.3 you can write the parental genotypes, for example, simply like this:

Example1 : AaAaAa X AaAaAa
Example2 : BbBbBb X BBbbBb
Example3 : CcCCccCcCc X CCCcCcccCc

But if you mark dominant and recessive alleles by different letters, then each group of polygenes in the notation of parental genotypes, you must conclude in the colon characters, like this:

Example1 : :RtRtRt: X :RtRtRt:
Example2 : :SwSSwwSwSw: X :SSSwSwwwSw:
Example3 : :<Dom><rec><Dom><rec><Dom><rec>: X :<Dom><rec><Dom><rec><Dom><rec>:
Example4 : :<Dom><rec><Dom><rec><Dom><rec>: X :<Dom><Dom><rec><rec><Dom><rec>: [Back to the top]

Polyploidy and nondisjunction of chromosomes

Q: How to get all possible combinations of gametes for diploids and polyploids, including those that are the result of nondisjunction of chromosomes?
A: To do this, you need each group of chromosomes (genes) in the parental genotype entry conclude in ampersands characters, like this:

Example1 : &XX&
Example2 : &AAA&
Example3 : &BBBB&
[Back to the top]

Q: Will the obtained ratio of gametes is valid, if we take into account all possible combinations of gametes?
A: Because the chromosomal nondisjunction occurs infrequently, the ratio of gametes in this case does not match reality, as well as the ratio of genotypes and phenotypes. [Back to the top]

Q: How to select only normal gametes in polyploids from all possible combinations?
A: In order to select only normal gametes you must to add percents characters in the end of the notation, like this:

Example1 : &XX%%&
Example2 : &AAA%%&
Example3 : &BBBB%%&
[Back to the top]

Q: How the program determines which gametes in polyploids is normal?
A:In the case of an even number of sets of chromosomes ploidy simply divided by 2. In the case of an uneven number, the ploidy is also divided by 2, but then to the obtained result added 0.5 and subtracted 0.5, and thereby we get two values.

Example1 : &XX%%& the normal gametes for diploids is haploid (X) (2/2 = 1(A)).
Example2 : &AAA%%& the normal gametes for triploids is haploid (A) and diploid (AA) (3/2 = 1.5; 1.5 + 0.5 = 2(AA); 1.5 - 0.5 = 1(A)).
Example3 : &BBBB%%& the normal gametes for tetraploids is diploid (BB) (4/2 = 2(BB)).
Example4 : &AAAAA%%& the normal gametes for pentaploids is triploid (AAA) and diploid (AA) (5/2 = 2.5; 2.5 + 0.5 = 3(AAA); 2.5 - 0.5 = 2(AA)).
Example5 : &BBBBBB%%& the normal gametes for hexaploids is triploid (BBB) (6/2 = 3(BBB)).
[Back to the top]

Q: How to select the gametes with specific ploidy?
A: If you want to select only a certain ploidy gametes, for this you have to write between the percents characters necessary value.

Example1 : &AAA%1%& if only the haploid gametes are needed
Example2 : &AAA%2%& if only the diploid gametes are needed
[Back to the top]

Q: Will the obtained ratio of gametes is valid, if we take into account only normal gametes?
A: The ratio of normal gametes is completely reliable and if you use the selection of normal gametes for both parental genotypes in the cross, then the ratio of genotypes and phenotypes will be also reliable. [Back to the top]

Q: Can I use the dominant and recessive notations of alleles for polyploids?
A: Yes, but in each group of polyploid genes you can use only one type of dominant and recessive alleles, like this:

Example1 : &XY%%& correct
Example2 : &AAa%%& correct
Example3 : &Bbb%%& correct
Example4 : &Aab%%& incorrect
[Back to the top]

Q: For example, what may be possible parental genotypes of polyploids?
A:

Example1 : &AAA%%& , &AAa%%& , &Aaa%%& , &aaa%%& for triploids
Example2 : &AAAA%%& , &AAAa%%& , &AAaa%%& , &Aaaa%%& , &aaaa%%& for tetraploids
Example2 : &AAAAAA%%& , &AAAAAa%%& , &AAAAaa%%& , &AAAaaa%%& , &AAaaaa%%& , &Aaaaaa%%& , &aaaaaa%%& for hexaploids
[Back to the top]

Q: Is it important the order of writing of dominant and recessive alleles for polyploids?
A: In contrast to the polygenic inheritance - order of writing of dominant and recessive alleles for polyploids is not important.

Example1 : &aAa%%&
Example2 : &aaA%%&
[Back to the top]

Q: Is it possible to mark alleles for polyploids with multiple letters?
A: Yes, for example like this:

Example1 : &<Dom><Dom><Dom><rec>%%& X &<Dom><Dom><rec><rec>%%&
Example2 : &<Dom><Dom><Dom><Dom><rec><rec>%%& X &<Dom><Dom><rec><rec><rec><rec>%%&
[Back to the top]

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