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Look up Calico [nofollow] & Tortoiseshell [nofollow] cats.Perhaps due to men getting a single dose of the X-Chromosome, and women getting a double dose of it, for the most part one X-Chromosome in females is inactivated. [nofollow] However, it is not always the same X Chromosome that is inactivated throughout the body.Since males get only a single X chromosome, there isn't any X-chromosome inactivation necessary, and thus the X chromosome calico genes would be uniform throughout the body.In the Calico/Tortoiseshell cats, in the females, they get some different X chromosome genes activated in different parts of the body causing the calico look. while two female cat clones share the same genes, they have different X Chromosome inactivation patterns, and thus different coats.As far as Genes, Genotypes, Phenotypes, and Inheritance Patterns, these were being determined long before DNA was discovered. Since determining the structure of DNA in 1953, there has been a lot of evidence to support DNA as carrying genetic information. as well as RNA, tRNA, and mRNA. Protein sequences match the DNA sequences. No doubt we will learn more about gene regulation in the future, and perhaps some formally considered "junk DNA" will be demonstrated to have some purpose.
Proteins don't self replicate independent of RNA/DNA. So, if one started with one cell with a certain set of proteins. Without the DNA, if the cell replicated a million times, there would be little left of the original protein.While there is a reverse transcriptase to convert from RNA to DNA, I don't believe there is any way to catalyse Protein/Protein copying, or Protein to RNA/DNA reverse transcription.Prions are unique among proteins in that they take normal proteins and force them into abnormal conformations, and thus cause disease. They are "inherited" by eating the brains of one's elders.There are also other proteins that catalyse protein folding, without which, the cells could not make the proteins that they need.Red blood cells (RBCs) as well as platelets are a unique group of anuclear cells. They can obviously perform vital functions in the body, but eventually wear out and must be replaced. After loosing the nucleus, they no longer can divide.Anyway, if proteins are required to initiate certain protein folding, perhaps there could be some proteins with multiple conformations that could be inherited, but as of now, only a few prions have been discovered.One should, of course, also mention that mitochondria, and chloroplasts carry their own DNA outside of the nucleus.In the case of mitochondria, while the sperm have their own mitochondria, only the mitochondria from the ovum are kept, and thus inherited through the maternal line.
DNA can't but RNA can independently self-replicate.Note that there is no complete block to proteins carrying information in biology, and some diseases such as scrapie and CJD are carried only by proteins. However, these known examples are rare exceptions, the vast, vast majority of inheritance is known to be via genetic means (also some other DNA-related epigenetic mechanisms such as methylation.)
Digression: Just because paternal mitochondria are not usually inherited does not mean that they can never be. As far as I know, nobody has tested if environmental stress can trigger paternal inheritance of mitochondria.
Proteins affecting inheritance in higher organisms is ridiculous. How would the signal get from your arm or whatever to the reproductive organs?
What's a motion pattern?
Quote from: Martin J Sallberg on 15/05/2013 13:30:05Digression: Just because paternal mitochondria are not usually inherited does not mean that they can never be. As far as I know, nobody has tested if environmental stress can trigger paternal inheritance of mitochondria.I thought mitochondria in sperm were only found in the tail, and that was why mitochondria DNA was inherited from the mother.
I suppose protiens can be considered to carry information by reason of having some function, but to equate this with molecules whose function is informational seems like equivocating 'information'. It may also be that proteins can be triggers for epigenetic changes, but that doesn't seem to be quite what is suggested here.Perhaps it would be clearer if the OP could describe a real-world example of proteins actively changing the genome?