The study of genomes, the entire set of genes in an organism.

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How is the size of a gene defined?

Is there an agreed definition as to how many nucleic acid bases constitute a gene? If not, why not? I'm not sure I understand how the exact sizes of genes are defined.
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2answers
768 views

How were the first primers made

I keep reading about how primers are useful in pcr -- they allow you to select a specific dna region. Similarly, in NGS or Sanger sequencing they give you a starting point. The primers I see are about ...
3
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2answers
202 views

What if a Point Mutation is seen in only half the coverage for its location?

I've been looking at some sequenced exomes and found an interesting point mutation that causes a Proline-to-Leucine amino acid change in the protein. This seems like it could have a big impact on the ...
3
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1answer
126 views

What is the genomic position of HLA-B*1502 variation?

I've searched the position and SNP ID of HLA-B*1502 variation. However, I couldn't find that where this variant exactly located on genome or HLA-B gene.
3
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1answer
140 views

Which part of a female mantises's DNA causes her to be a few times larger than a male mantis?

Which part of a female mantises's DNA causes her to be a few times larger than a male mantis? Do other species have that part of DNA?
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1answer
80 views

Can both the overlapping genes (in opposite strands) produce proteins?

I have recognized that both the forward and reverse transcripts from a genomic location code for protein products. Both do occur/express in the tissue of interest. In order to eliminate by chance ...
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1answer
2k views

What is the difference between Single Nucleotide Polymorphism (SNP), Mutation and Structural Variation(SV)?

This is a question which plagues many people and today I was wondering it myself while writing a grant. Indeed, I've seen many people use the terms interchangeably, but they are all very different ...
3
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1answer
411 views

How might gene clusters like the lac operon evolve?

The obvious answer for a gene cluster is gene duplication and mutation of one or both genes. But the genes in the lac operon seem not be so functionally/structurally similar (as compared to the Hox ...
3
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2answers
84 views

Microbiome Data

How is it possible to access microbiome data like that found here? I'd like to perform analyses on similar type of data, but cannot find OTU data like that at the Human Biome Project. Thanks for any ...
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1answer
55 views

Perplexing by the way of estimating the shared or different genes between humans and chimps

We share 98.5% genes with chimps (it means we have 98.5% same DNA sequeces ),so there is about one percent difference .It means we can approximately differ from them by one base pair every hundred ...
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2answers
144 views

Do transposons usually jump from one chromosome to another?

If it is usual occurrence, does it mean that my one gene can change its location from one chromosome to another?
3
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3answers
128 views

Publicly available genotype data?

I am a statistician and I'd like to test my new method on biological data. For this I am looking for genotype data for a number of individuals. That is, I am looking for something like this: ...
3
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1answer
120 views

Sex biased gene expression in the X chromosome

It has been shown that the X chromosome is frequently enriched for female biased genes, and has a deficit of male biased genes. For example in this paper, and this one. However, I'm struggling to ...
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1answer
35 views

Exon skipping in mammals

I've heard from several sources that the predominant form of alternative splicing (at least in mammals) is exon skipping. However, my personal evidence is only anecdotal: I've heard it and read it, ...
3
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2answers
109 views

Sequence alignment scoring

The following table is from Deonier's text Computational Gene Analysis at p. 152. This is an exercise in global sequence alignment and scoring of alternative sequences. The text proposed a solution (...
3
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1answer
49 views

What is the genetic distance where linkage can be ignored?

I heard several times that two SNPs, that have at least 1'000 nucleotides between them, can be seen as 'unlinked' due to frequent recombination events. I also once saw a paper showing a graph "degree ...
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1answer
49 views

Are there any major noticeable limitations to genome sequence compression methods that use reference templates?

Recently, I have been researching about big data analytics in biochemistry, and started wondering about how genome sequence compression could affect analysis. Of all the method listed on the ...
3
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1answer
47 views

Finding confidence level of miRNA disease associations

I'm an undergraduate computer engineering student, and I have a project about bioinformatics. In this manner, I need to find prediction( or association I'm not sure the correct terminology) confidence ...
3
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2answers
191 views

Why only heterogeneous SNVs for validation using genotyping arrays?

I am trying to validate the variants I found using whole genome sequencing . The standard practice, I have seen in the two publications below were to check for the number of heterozygous SNPs called ...
3
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0answers
68 views

RAD sequencing: choosing the appropriate enzyme?

I’m studying Darwin’s finches genome and I say in some articles that the researchers used restriction enzymes to cut the DNA in their double digest RAD protocol. They are using EcoRI and MseI (GAATTC ...
3
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2answers
79 views

How much genomic variation one usually find within a given bacterial species?

If I find the exact starting position (say 1152471) of the coding sequence of a given gene in the genome of a bacterium, is the genome of the bacterium in general stable enough so that I can expect to ...
3
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0answers
58 views

Degree of dosage compensation in Drosophila melanogaster

In this paper the authors state that the dosage compensation seen in Drosophila is approximately twofold, but they do not provide any source or numbers (as far as I can see) for this. What is the mean ...
2
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2answers
221 views

How does the telomere repeat sequence vary in Eukaryotes?

Question: How does the telomeric repeating sequence vary in non-vertebrate Eukaryotes? If you know the repeating sequence of a given species I would appreciate hearing it. Background: Telomerase is ...
2
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2answers
222 views

In Sanger sequencing, why do we resort to cloning? Why doesn't PCR suffice?

I understand that in Sanger sequencing we can clone our fragments with the help of e.g. bacteria to make multiple copies of our fragments for further analysis. I also understand cloning can be a ...
2
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2answers
1k views

How many recombination events are there per generation in humans?

I'm looking for a reference that tells me how many recombenation events occur in humans from one generation to the next. Assuming that the human genome is a 3.3 GigaBases long DNA sequence, how many ...
2
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1answer
67 views

Are dogs affected by dwarfism?

My husband and I noticed a dog today that looked like a smaller version of a purebred Border Collie, although it didn't appear to be a puppy. It made us wonder if other animal species experience ...
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1answer
128 views

Whole genome sequence analysis software

Please help to choose Bioconductor R packages and other software for the whole genome sequence data analysis and, in particlular, the goals of false discovery mutation rate, mutations exclusion, ...
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217 views

Accuracy of a particular genetics test

I am a newbie in biology and I am simply trying to discover the field of genomics. Consider the question - Are genetic tests accurate? I don't believe they are as the genes may not provide the ...
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2answers
34 views

Function and expression of pseudogenes

Can pseudogenes be transcribed into mRNA and translated into functional proteins, or should they be regarded as functionless mutated genes?
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65 views

Database of medically validated SNPs

I'm looking for all possible sources of clinically tested human SNPs. There is a handful of databases that store SNPs (like dbSNP), but I only need those that have validated presence/absence of ...
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1answer
53 views

Understanding conclusions that functional regions are under negative selection?

I am reading in notes for a comparative annotation lecture that : all DNA is subject to mutations most functional regions are under negative selection (ie., mutations are often deleterious) The ...
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2answers
78 views

In genome research, what is the problem in Mapping that may be caused by reads being too short?

In the following scenario: You were given short sequence reads of plant RNA obtained from a next-generation sequencing machine (fragments of 20–30 nucleotides in length). You attempt to map them back ...
2
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1answer
80 views

Need help distinguishing between a primary and secondary source

I am trying to figure out if the following article is a primary or secondary source. I'm leaning towards secondary but here are my cases for both. Primary: Published in a peer-reviewed journal....
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2answers
49 views

How does one find the corresponding SNPs in the pair of chromonosmes in a FASTA file?

You might say I'm an amateur bioinformatician, or trying to become one. I have a BAM file, from which I have succeeded, using UGENE , in extracting consensus data in FASTA format. I now see a single ...
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2answers
110 views

Databases for metabolic pathways of human disease

Which databases contain the metabolic pathway of human diseases? I have searched Metacyc and KEGG but didn't find the appropriate metabolic pathway.
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24 views

How does one apply Bayesian inference to quantify a read the deeper you sequence?

For NGS sequencing technology, the "deeper" you sequence given fragments, the more certain you are of what is being sequenced. This sounds like a simple application of Bayes's Rule. What is the ...
2
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1answer
369 views

What is pQTL and why do we need eQTL?

eQTLs are genomic loci that contribute to variation in expression levels of mRNAs (wikipedia). There is data out there that shows that ~60% of the time, the amount of mRNA in a cell is directly ...
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0answers
17 views

Why there are two rounds of cytosine de-methylation in mammalian development?

I assume that the key biological meaning of cytosine de-methylation during germline development in germline progenitor cells is to reset imprinted genes and then set methylation pattern on these genes ...
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0answers
42 views

What is the best way to perform ultra-deep targeted sequencing of few samples?

I performed recent whole genome/exome sequencing in tumor samples and now I would like to take a few of these variants (say maximum 50 amplicons) to: 1) Validate them in the original samples 2) ...
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0answers
43 views

Where can I upload non-human Genotype data?

I have genotype data from few chicken population and I want to (need to) upload them somewhere online with free access. I have searched the web but I haven't found any place for non-human genotype ...
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0answers
45 views

Genome-wide methylation analysis: sources of technical error?

We are doing a genome-wide analysis of methylation via bisulfite sequencing for an insect species. Previous experimental techniques have suggested the presence of methylation in this organism, ...
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0answers
41 views

Assembly reconciliation

We have some bacterial genomes that were assembled using Spades, they were sequenced with and IonTorrent PGM. There are many assemblers and they give different results. I was interested in a tool ...
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0answers
107 views

Predicting host-pathogen gene interaction networks

Background What we have are: ~20 genome sequences for a host species that come with gene annotations Several sequenced genomes for parasite/pathogens of these hosts Question What are the ...
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0answers
186 views

Too few transcripts from transcriptome assembler Oases

I am trying to run Oases for transcriptome assembly. The result is far from expected, so I would like to ask whether I am running it in a right way? Thanks. Here is my running command: ...
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2answers
168 views

How does high-fidelity of DNA replication depend on the formation of hydrogen bonds?

Replication has an error rate of less than 1 in 100 million. DNA polymerase forms H-bond with the H-bond acceptor atoms in the minor groove. <-- enhance fidelity here? Binding of the triphosphate ...
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1answer
105 views

How can I download a gene sequence from GenBank (NCBI)? [closed]

Could you tell me the steps to find and download a gene sequence from GeneBank? I would appreciate your help.
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1answer
64 views

Where can I find DNA Sequence data for colon cancer

I am a computer scientist studying pattern recognition, and I am hoping to do some supervised learning on colon cancer. Unfortunately, I'm having a heck of a time finding DNA data in the following ...
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2answers
178 views

what does sequences overlap indicate

what does it mean if different protein sequences overlap upon multiple alignment, are they the same, do they have a common ancestor, are they recombinants of each other and how does one go on to ...
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1answer
53 views

How are geneticists able to isolate gene functions?

As an example, this Scientific American article describes a known area in the dog genome that metabolizes carbohydrates. How is it that researchers are able to determine specific functions such as ...
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2answers
38 views

How do biologists quantify “gene expression” in experiments?

I've read papers which contain statements such as "control of gene expression is critical in biological processes". How exactly does one quantify "gene expression"? Isn't gene expression an umbrella ...