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102 votes
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Does the string "...CATCAT..." appear in the DNA of Felis catus?

The Felis catus genome has been published, annotated, and updated quite a bit since 1996, including spans of so-called intergenic regions, which are basically scaffolding and other structures, along ...
MattDMo's user avatar
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66 votes

Does the string "...CATCAT..." appear in the DNA of Felis catus?

While Matt's answer is perfectly correct, it is important to note that the sequence $(CAT)_n$ in DNA is not restricted to cats, and you would expect to find it anywhere. For example, searching the ...
March Ho's user avatar
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16 votes

Does the string "...CATCAT..." appear in the DNA of Felis catus?

To augment the other answers, let's compute the probability of CATCATCATCAT occurring in random DNA sequence. Cat DNA length is 2.7 gigabases (source), and there are 4 possible bases. For 1 CAT there ...
jpa's user avatar
  • 301
10 votes

Does the string "...CATCAT..." appear in the DNA of Felis catus?

So, there are a few great answers here already, but it seems nobody addressed an interesting part of your question: GEB was published in 1978 and the genome of Felis catus was not sequenced until many ...
Owen Versteeg's user avatar
9 votes
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What causes cells to inactivate one X-chromosome?

Even a male cell can count the number of X chromosomes. (Lee et al. 1996; Cell 86: 83-84) When X inactivation is getting started the two chromosomes "kiss" - a process that lasts for a couple of ...
Retardi Grade's user avatar
6 votes
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What is the most genetically complex organism?

Edit: I would define genetic complexity as either genome size or number of genes. Either answer or information would work. Largest genome: Paris japonica, a rare plant. Its genome is 149,000,000,000 ...
S Pr's user avatar
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6 votes
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semantical meaning of positions of letters in genomic sequences

I would recommend thinking about DNA sequences more like words and sentences in a book than bits in a digital data file. If you're reading a book and come across: The quick brown fox jumps over the ...
Bryan Krause's user avatar
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5 votes

Are there parts of DNA that do not have genes?

Most the genome is not coding for proteins. Here is a pie chart of what the human genome is made of As you can see, only 1.5% of the human genome codes for proteins. The term gene is often a bit ...
Remi.b's user avatar
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5 votes
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Do all chromosomes in one human body contains same genome?

Yes, all cells contains the same genome. This is because, for a given individual, all of its cells comes from the zygote, a singular cell formed after fecondation of the maternal ovum and paternal ...
Eliane B.'s user avatar
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5 votes
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Giga base or Giga byte

This refers to base pairs. File size has no particular meaning beyond practical considerations, given that it depends on the format. (For example, 2bit files use 2 bits per base, as the name ...
Eliane B.'s user avatar
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5 votes
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Difference between NCBI's /genomes and /1000genomes

The simplest difference is the scale and range. The aim of 1000 genome project was to provide comprehensive library of human genetic variation. DNA of individuals coming from different ethnic groups, ...
hibernicah's user avatar
5 votes
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Protein-coding introns in mitochondrial genomes

Mitochondrial genomes differ greatly in size, coding potential and even whether they are circular or linear. Mammalian mitochondrial DNA is small (11–28 kbp) and intronless. However the mitochondria ...
David's user avatar
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5 votes
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Understanding Contig NG50

If you arrange your contigs from longest to shortest, what is the shortest contig in the smallest subset of contigs that covers at least half the expected genome length? An example with arbitrary ...
acvill's user avatar
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5 votes

What is "Correlation of growth" according to Darwin and was he correct about it according to modern science?

[...] correlation of growth, as Darwin called it. This law states that the specialised forms of separate parts of an organic being are always bound up with certain forms of other parts that apparently ...
S Pr's user avatar
  • 6,272
4 votes

What is the strand specificity of a reference genome?

The + and - is a bioinformatics classification. The reference sequence is by default the + ...
WYSIWYG's user avatar
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4 votes
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Where can I find the genome of the L-strain coronavirus and the S-strain coronavirus?

Article links to this publication which has all the information needed: https://academic.oup.com/nsr/advance-article/doi/10.1093/nsr/nwaa036/5775463 It is mentioned in the paper that: Although we ...
m4rio's user avatar
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4 votes

Why do microarrays require a priori knowledge of the genome?

If the query genome is unknown, a microarray cannot be made for a target species. Microarrays have DNA fragments of what you want to amplify on them. Those fragments must be known. From nature: DNA ...
pascal's user avatar
  • 604
4 votes

Has life on Earth explored the entire space of genomes?

The answer to this question is very much no. Genomes are of arbitrary length and structural organisation (i.e. ploidy), so there isn't a fixed number of 'slots' that different base-pairs could inhabit ...
user438383's user avatar
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4 votes
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Do we know the genome contains all the information necessary for embryonic development?

The second quote is about stochastically determining which side is the "head" and which is the "tail", effectively, which occurs by positive feedback of an existing gradient. This ...
Bryan Krause's user avatar
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3 votes
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Personal Genomic Data Samples

Here is the link to the 1000 Genomes project, all the data is available for download. They already have a comprehensive list of SNPs as well. It is not the only project around but it is definitely the ...
alec_djinn's user avatar
  • 3,108
3 votes

All somatic cells contain the same genome, then how does it knows that it should develop into a specific organ?

The answer to your question is not really know yet and there is whole scientific field dedicated to it: developmental biology. I'll try to explain the basics however: Like you described the identity ...
Nicolai's user avatar
  • 4,391
3 votes

What is the strand specificity of a reference genome?

Answer There is no such thing as a positive or negative strand for a genome (reference or otherwise), for the simple reason that the genomes of almost all organisms contain genes in both orientations, ...
David's user avatar
  • 26.2k
3 votes

What does it mean by “end effects can be ignored”

They are considering a model of a DNA sequence of quasi infinite size. They consider a case where the DNA sequence is so long that the fact that it has ends will only negligibly affect the conclusions ...
Remi.b's user avatar
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3 votes

What would an organism be like if its entire genome "worked"?

Your question is closely related to the concept of minimal genomes, in which researchers attempt to understand the significance of genes by removing everything that isn't strictly necessary, which ...
jakebeal's user avatar
  • 7,007
2 votes
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Does GC content determine codon bias or does codon bias determine GC content

Think about it this way, the G-C content is averaged over the entire genome, and varies between different species. Whether you are dealing with prokaryotes, with relatively compact genomes, or with ...
mdperry's user avatar
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2 votes
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How much genomic variation one usually find within a given bacterial species?

Genetic variation within bacterial species can be much higher than one might expect. First, this can be a difficult question to answer quantitatively because even just testing whether two strains ...
Patrick B.'s user avatar
2 votes
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How two genomes adopt when cell goes to recipient's body from donor's body?

My previous answer was to the original question which focused on red blood cells which do not contain DNA. Now the question has been revised to focus on tissue transplantation, where the cells do ...
David's user avatar
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2 votes

Which organism has the smallest genome length?

Both Mycoplasma genitalium and Nanoarchaeum equitans are obligate parasites / endosymbionts. This means that they depend heavily on their host to support their vital functions and they have lost many ...
Alamot's user avatar
  • 21
2 votes
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Why do two different E. coli reference genomes have different lengths?

U00096.2 is an updated version of U00096.1; you should preferably use the former for your analysis. In fact, even U00096.2 has been updated. The latest version is U00096.3. In general, the number ...
WYSIWYG's user avatar
  • 35.6k
2 votes
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Can a gene-expression or epigenetic 'user-history' be found in the body?

Main question Does the body store a history of these expressions? Do the chromosomes (or some other part) of an older organism store a 'user-history' of which genes where previously activated ...
WYSIWYG's user avatar
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