List of Recessive Traits

[Sam_Skunkman]

Brownpants,
FYI, I have clones of whorled phyllotaxy plants, both males and females. And I do agree that males are much more common then females. Maybe by 10 to 1.
-SamS

 

[zamalito]

I always assumed that whorled females were so much more common than males is because there were separate genes for whorled males and whorled females. Have you noticed otherwise sam?

 

[Sam_Skunkman]

I used to think Fasciated is a mutated normal gene and not inheritable. That said I have tried repeatedly to make progeny with fasciated mothers and fathers but none of the progeny have ever expessed the trait. If it was dominate then all of the progeny should of been fasciated, while if it was recessive 1/4 of the progeny should of been fasciated. But I never got any and I made several crosses with different fasciated parents. And I used the part of the plant that was definately fasciated. I have a Sativa clone that is fasciated, that does not show any sign of being fasciated until it is over 1 meter tall then everything above that is fasciated. I have several dried stems that are 10+ foot tall, and flattened from the fasciated effect. They look cool but this trait is of no use to seed or bud producers as the buds produced are inferior with small bracts much less resin a much smaller total yield.
Has anyone else made fasciated female X fasciated male crosses? What were the results? Any fasciated progeny?
Also about Whorled Phyllotaxy, I did make a few crosses but also I never got any progeny with three sets of branches like the two parents, but I only tried a little.
-SamS

 

[TGT]

I have a plant from seed that I just sprouted about a month ago and it has crumpled leaves and expresses it even now as it is getting larger. Is this a mutation and considered a whorled effect? I don't know much about mutation so I thought I would ask. Also, would this be seen in successive generations or are mutations usually lost after the first generation? Thanks in advance and sorry for my ignorance.

TGT

 

[zamalito]

I did some experiments with what sounds like that same deformity you mentioned. It was on some ghanaian stock I'd gotten and didn't start until about 18"-2' tall. I called it the ribbon stemmed trait. The flowers had a weird look where they were 3" wide but 1" thick. Like you said no f1's or f2's showed this trait.

However with trifoliate males exhibiting the more standard trifoliate trait x non-trifoliate females used when inbreeding on a c99 line I'd obtained about 25% of the males in the following generation were trifoliate within the cotyledons or subsequent two nodes so I'm guessing it's recessive but I never took that line past that generation to be certain. There is definitely some degree of heritability with this trait among males.

 

[A.N.Other]

THC/CBD Inheritance

The Inheritance of Chemical Phenotype in Cannabis sativa L.(2002)

Etienne P. M. de Meijer, Manuela Bagatta, Andrea Carboni, Paola Crucitti,
V. M. Cristiana Moliterni, Paolo Ranalli and Giuseppe Mandolino

*HortaPharm B.V., 1075 VS, Amsterdam, The Netherlands and Istituto Sperimentale per le Colture Industriali, 40128 Bologna, Italy

Abstract:

Four crosses were made between inbred Cannabis sativa plants with pure cannabidiol (CBD) and pure ∆-9-tetrahydrocannabinol (THC) chemotypes. All the plants belonging to the F1’s were analyzed by gas chromatography for cannabinoid composition and constantly found to have amixed CBD-THC chemotype.

Ten individual F1 plants were self-fertilized, and 10 inbred F2 offspring were collected and analyzed. In all cases, a segregation of the three chemotypes (pure CBD, mixed CBD-THC, and pure THC) fitting a 1:2:1 proportion was observed. The CBD/THC ratio was found to be significantly progeny specific and transmitted from each F1 to the F2’s derived from it. A model involving one locus, B, with two alleles, BD and BT, is proposed, with the two alleles being codominant. The mixed chemotypes are interpreted as due to the genotype BD/BT at the B locus, while the pure-chemotype plants are due to homozygosity at the B locus (either BD/BD or BT/BT). It is suggested that such codominance is due to the codification by the two alleles for different isoforms of the same synthase, having different specificity for the conversion of the common precursor cannabigerol into CBD or THC, respectively. The F2 segregating groups were used in a bulk segregant analysis of the pooled DNAs for screening RAPD primers; three chemotype associated markers are described, one of which has been transformed in a sequence-characterized amplified region (SCAR) marker and shows tight linkage to the chemotype and codominance.

Full study:

http://www.genetics.org/cgi/reprint/163/1/335.pdf

 

[Brownpants]

Whorled Phyllotaxy plants are more interesting than I first thought they were. Sounds like the genes involved still have a connection with sex linkage because of the male to female ratio of 10:1. The fact it occurs in females at all indicates it is associated with the "X" chromosome rather than the "Y" chromosome.
I am puzzled by the lack of "whorled" progeny, especially if none showed up in the F2 generation. A Rare recessive X-linked allele can hide from F1 generations if a "Whorled" male was used in the cross, but it would show up in the F2. A "Whorled" female would produce "Whorled" progeny in the F1 generation, especially in the males (nearly 100%). I suspect more than one gene is involved in this phenotype. The affected plants aren't polyploids (3n,4n) are they?

A.N.Other - Thanks for posting the link.

 

[BeAn]

Zamilito, Definantly hear what your saying about the Ribbon mutation..I had a Floater plant that had a stem as you described, it was from an F1 bx to the mother.. Flo x Jacks cleaner x Blueberry..

Lots of good info here.. Nice one peeps..

 

[Guest]

Some of this isnt even sinking in yet! Fantastic thread guys love the info

 

[Sam_Skunkman]

Brownpants,
Why do you think whorled is sex linked?
FYI, the whorled crosses I made used whorled males and females. Same with the fasciated crosses. Neither gave progeny like the parents.
The articles I read today say the fasciated is both mandelian and non-mandelian inherited, at least in other species. I thought they were non inherited mutations.
And no polyploids were used.
Some Fasciated rreferences:
http://faculty.ucc.edu/biology-ombrello/POW/fasciated_plants.htm
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1469-8137.1929.tb06751.x

http://links.jstor.org/sici?sici=00...ww.springerlink.com/content/m5v501qw383w1532/
http://www.springerlink.com/content/w3156p747t1876q7/
http://aob.oxfordjournals.org/cgi/content/abstract/98/4/715

http://links.jstor.org/sici?sici=0028-646X(19290522)28%3A2%3C150%3ATSOFPO%3E2.0.CO%3B2-K
http://links.jstor.org/sici?sici=0006-8071(193009)90%3A1%3C116%3AIFAFMC%3E2.0.CO%3B2-Q
http://www.springerlink.com/content/m5v501qw383w1532/
if the link don't work paste into a browser.
-SamS
PS I did make a mistake (fixed now) with whorled/fasciated. I know the difference but when I type fast and smoke to many big bongs I do get fuzzy....

 

[Brownpants]

SamS - Interesting articles about fasciation of different plants. Lots of interesting points. It made me think more than ever that something was wrong with the assumptions I made about the observations of Whorled Phyllotaxy.

I assumed the environment was constant for all plants involved and their progeny. But, unless you were open pollinating, you would have moved the males to a new location, a different environment. This would give the appearance of a sex-linkage, but it might be more to do with the differences in environmental conditions between the sexes. ex) maybe you moved the male plants inside and left the females outside. This would create vast differences in environment between the plants involved. The ideal environment for this experiment would be indoors, pest free, same type of lights, hydroponically grown with a shared reservoir and maybe a divider separating the males from females.

If environmental conditions can be made constant and there is still a 10:1 ratio of males to females exhibiting this trait, then sex-linkage of the "x" chromosome can not be denied. Something is linked to males exhibiting this trait over females, there is no other way to explain the high ratio of 10:1.
The mendelian ratio for recessive phenotypes (1/4) found in F2s applies to autosomal inheritance (non-sex chromosomes). Sex linked inheritance exhibit a different set of characteristics.

If I was to make a guess at this point (hypothesis), this is what it would be (making lots of assumptions here). I think there is a recessive gene on the "X" chromosome that is rare and sex linked. This gene is detrimental to the health of the plant and is naturally selected against in nature. This gene is sensitive to an environmental condition not yet identified (UV, PH, Temp. etc). The lack of progeny exhibiting this trait might be do to the absence of the environmental trigger during a critical part of the growth cycle.

Did you notice a decrease in seeds being produced with these crosses, or a high level of mortality?

-BP-

 

[Daytripper]

If I was to make a guess at this point (hypothesis), this is what it would be (making lots of assumptions here). I think there is a recessive gene on the "X" chromosome that is rare and sex linked.

My opinion is that its located on the Y chromosome, one reason its more often seen in male plants, its less often seen in females for several reasons.

Females show this when chromosome segments are exchanged between X and Y. There are a lot of chromosome blocks and this one is not always exchanged. This explains why its more commonly seen in males but not sex linked, if it were sex linked this would never be seen in females.

A guy can't breed a line that shows this trait because of crossing over, a type of recombination that occurs on a single chromosome with little to no crossovers occurring on the Y chromosome of cannabis.

 

[zamalito]

It never crossed my mind that the ribbon stemmed plant I had could be crested. I have been colecting crested hallucinogenic cacti for a couple years. I have several crested williamsii's (peyote) and san pedros as well as my beloved caespitosa williamsii. I actually made a post in this forum asking for advice on how to breed a true breeding crested peyote and why when I tried to breed a crested williamsii I could never get the trait to occur with increased frequency. I guess now I know why. Thanks Sam! I also have a ansel adams (I know its a bit cliché) picture of a crested seguaro on my wall.

 

[Brownpants]

If I was to make a guess at this point (hypothesis), this is what it would be (making lots of assumptions here). I think there is a recessive gene on the "X" chromosome that is rare and sex linked.

My opinion is that its located on the Y chromosome, one reason its more often seen in male plants, its less often seen in females for several reasons.

Females show this when chromosome segments are exchanged between X and Y. There are a lot of chromosome blocks and this one is not always exchanged. This explains why its more commonly seen in males but not sex linked, if it were sex linked this would never be seen in females.

Daytripper - Do you know what sex linkage means?

It means a gene is located on a sex chromosome. "X" or "Y"

Sex linkage is seen in females, it is just more rare if the trait is recessive because it can be masked by the other "x" chromosome. Your explanation of a cross-over doesn't take into account that the female has another "X" chromosome from the maternal side.

I prefer to look at the simplest, most likely explanations before moving on to the more complex scenarios. There is a definite need for more research data on this topic before making any final conclusions.

A guy can't breed a line that shows this trait because of crossing over, a type of recombination that occurs on a single chromosome with little to no crossovers occurring on the Y chromosome of cannabis.

This makes no sense and contradicts what you said earlier. The data doesn't support your explanations.

 

[Guest]

What data?

 

[Daytripper]

Daytripper - Do you know what sex linkage means?

It means a gene is located on a sex chromosome. "X" or "Y"

Sex linkage is seen in females, it is just more rare if the trait is recessive because it can be masked by the other "x" chromosome. Your explanation of a cross-over doesn't take into account that the female has another "X" chromosome from the maternal side.

I prefer to look at the simplest, most likely explanations before moving on to the more complex scenarios. There is a definite need for more research data on this topic before making any final conclusions.



This makes no sense and contradicts what you said earlier. The data doesn't support your explanations.

Could it be YOU don't understand what crossingover is?
edit: directed at both NepHaze and Brownpants.

Recombination on one chromosome.

Completely different from two chromosomes EXCHANGING chromosome segments.



"crossing over, process in genetics by which the two chromosomes of a homologous pair exchange equal segments with each other. Crossing over occurs in the first division of meiosis. At that stage each chromosome has replicated into two strands called sister chromatids. The two homologous chromosomes of a pair synapse, or come together. While the chromosomes are synapsed, breaks occur at corresponding points in two of the non-sister chromatids, i.e., in one chromatid of each chromosome. Since the chromosomes are homologous, breaks at corresponding points mean that the segments that are broken off contain corresponding genes, i.e., alleles. The broken sections are then exchanged between the chromosomes to form complete new units, and each new recombined chromosome of the pair can go to a different daughter sex cell.

Crossing over results in recombination of genes found on the same chromosome, called linked genes, that would otherwise always be transmitted together.

Because the frequency of crossing over between any two linked genes is proportional to the chromosomal distance between them, crossing over frequencies are used to construct genetic, or linkage, maps of genes on chromosomes. Mutations, temperature changes, and radiation all affect crossing over frequency. Under the microscope, a crossover has the appearance of an X and is called a chiasma." - columbia university

 

[Guest]

thanks daytripper

 

[southwind]

okay maybe we should try get along

okay maybe we should try get along

Greetings


These topics can invite some dissention at times.

The truth is that Genetics is a difficult subject for a lot of people, most these days think it is so far beyond them that there is no hope of understanding it.

And especially in the specialized field world we live in it is impossible for one person to be more than a generalist in many subjects.

Remember that "genetics" started as "animal/plant husbandry"
regular farmers bred their best stock together and hoped to get a better stock.

In this age we still dont have a chemical analysis of chromosomes that will tell us if a gene is dominant or recessive or co-dominant...etc..etc.

there is still some argument among the Geneticists themselves about how it all works.

Dissention among us as amateurs is inevitable.

If you want to start a REAL argument lets talk about Lamarck


Anyway here is some good info on how to track genes with a Mendellian Box
or look up Chi square
this is the classic and still used method to find out what your ominant and recessives are.

http://72.14.253.104/search?q=cache...sive+dominant+genes&hl=en&gl=us&ct=clnk&cd=15

http://waynesword.palomar.edu/lmexer4b.htm


. In rabbits, black fur (B) is dominant over brown fur (b). Consider the following cross between two rabbits.





peas

 

[southwind]

ACCESS TO OLD GENETICS

ACCESS TO OLD GENETICS

Does anyone even have access to old world indica?

 

[Daytripper]

We should try to get along as we are family, but families are so close they often argue with other family members on subjects central to our wellbeing, future and existence.

The truth is that Genetics is a difficult subject for a lot of people, most these days think it is so far beyond them that there is no hope of understanding it.

Learning to read is much more difficult than a basic understanding of genetics. We all learned to read and I for one recall learning to read required effort , practice and time. 15 to 30 minutes a day and in only 3 months I was the best reader in my grade.

Buy a college level text, study like your future depended on it and in 3 months you will be able to look back and know you've made a giant leap forward.

Posting and discussing is practice.

Brownpants if it were sex linked it would be only 1 gene and easy to make a female line that had this trait using a backcross.

I could list several more reasons like the number of females showing this trait should be the square root of the number of males showing this trait.

If 1/20 females show the trait every population having 400 males showing this trait would have 20 females with the same trait. 20 being the square root of 400.

I've been wrong more times than I care to admit to.