Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics, particularly chromosomes and DNA.
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Are there differences in DNA between humans of today and humans from 2000 years ago?
Are there any significant differences in our genome compared to the genes of our ancestors from 1000-2000 years ago?
And if there are significant differences, do they result in significant ...
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Origin, or source, of rhesus negative in human blood
This is my first post here, so please be gentle. I recently learned that I have Rh- blood (I'm A-), and was idly looking into blood types on Wikipedia. I was surprised to find that relatively few ...
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Predicting progeny of recessive mutations using recombination
I was asked this question on a test and got it wrong, but I'd like to know how to do it. The answers are shown in the blanks below:
You are studying two recessive mutations in the fruit fly D.
...
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Pedigree Probability of Autosomal Recessive Trait
Here is a pedigree:
The trait is autosomal recessive.
The question is: What is the probability that the bottom 2 people (4 and 5) have a child with the trait?
I tried doing ...
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Genetic carrier Pedigree of Recessive Traits
A human male and female couple with normal colored ears discover that, in both of their families, their fathers (who have normal ears) each had siblings with red ears. Red ears is a rare autosomal ...
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Do white Australians have a distinct look?
Background
I've heard from many people working in tourism or similar industries that, white Australians can be recognized as Australian solely by their facial features. Being Australian myself I've ...
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Why some genes are dominant to each other? What is the mechanism behind it?
If i have a brown eye gene which encodes the protein that is responsible for the brown color, and have a blue eye gene either, what is the reason that my eye color is brown? How does one gene ...
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How to create a collection of anonymous sequences for teaching and testing? [closed]
I am looking for a large collection (>1000) of sequence files (eg. FASTA) from any real organism or a tool to create such a collection.
The sequence files would be used for teaching and for testing ...
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Can genetically modified genes jump to bacteria in the eater's intestine?
The Guardian ran an article a while back talking about GM gene's jumping to bacteria in an eater's intestine. Has other research confirmed this phenomenon?
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What is the advantage of circular DNA in bacteria?
From what I understand, bacteria have circular DNA. What advantages does it have over linear strands like for eukaryotes?
Do there exist bacteria with more than one ring of DNA?
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Can two humans with 44 chromosomes produce viable offspring?
It is known that there are very few individuals having 44 chromosomes, not the usual 46 chromosomes.
One example is a male in China: the first article, the second article.
The other is a female in ...
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Is there any reason for the variation in mitochondrial DNA size?
As my textbook An Introduction to Genetic Analysis points out, yeast mitochondrial DNA has approximately 78 kb of genetic data, while the human mitochondrial DNA contains 17 kb. Is there any evolution ...
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What is the distinction between F' plasmid and R plasmid?
Is there a difference between an F' plasmid that has taken up a chromosomal gene that conveys antibiotic resistance, and an R plasmid? Is a bacterium containing an R plasmid and yet lacking an F+ ...
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Are homozygous carriers of the CCR5-Δ32 allele fully immune to all known strains of HIV?
Or is there documented evidence of even one homozygous carrier contracting HIV and staying infected?
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Does the genetic expression of specific physical traits ever correlate to behaviour?
Over at skeptics, there were a couple questions asked as to the correlation of specific physical traits in relation to personality/behaviour. For instance, the simian line as well as red hair. Now, ...
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How is eye color in humans inherited?
In high school we studied the inheritance of eye color, as it was explained to us in the most simple way: blue eye color is a recessive, monogenic, autosomal trait. Now I know that it is a bit more ...
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How do members of cryptic species know who to mate with?
According to Wikipedia:
In biology, a cryptic species complex is a group of species which
satisfy the biological definition of species—that is, they are
reproductively isolated from each ...
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Overlapping genetic information in eukaryotes
In my research, I look at a lot of gene predictions / annotations. Frequently, I see loci where multiple gene models overlap. I haven't taken a systematic approach to analyzing these cases, but I do ...
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Why 20 amino acids instead of 64?
This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 20 amino ...
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What is the smallest number of amino acids required for life?
Is there any hypothesis on the minimum number of amino acids required for life?
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What are the different ways an exon gets spliced?
Exons are produced by more than one mechanism, e.g. splicing out introns after transcription, if I remember correctly. Please list all mechanisms.
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What are the function(s) of Alu elements in the cell?
My 2008 biology book (1) states that some 10% of the human genome consists of relatively short (~300 nucleotides long) Alu elements which do not code for proteins but many of which are transcribed ...
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What is the functional and structural distinction between core (H2A, H2B, H3,H4) and linker(H1/H5) histones?
Many explanations of histone biochemistry isn't quite elucidating for the undergraduate student. How does histone structure (dimers, octomers) relate to their specific functions as core or linker ...
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Could Junk DNA be used as a Turing Machine by nature?
In what ways has DNA been studied to see if there a "programmable" aspect to it?
Has nature produced anything resembling a Turing machine within the cell, perhaps using the "junk DNA" as its code? I ...
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Why was it so hard to decode the corn genome?
My teachers growing up told me it was impossible to decode the maize genome. But yet its been done.
Why was decoding the genome so significant, and what made it so difficult?
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Smallest viable reproducing population
What is the smallest viable reproducing population, such as in a human population. By viable I mean a population which keeps genetic defects low (enough).
A very strongly related question: what is ...
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What do the variants on the PolyT sequence mean?
My son has been diagnosed with Cystic Fibrosis. I am not looking for medical advice regarding his condition, but I am very interested in understanding the genetic causes of his condition.
In ...
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How many people's DNA were involved in the compilation of the reference human genome?
I know that the reference human genome is complied from DNA portions from different people, most of whom were European. Do you know how many of them were involved? Do you know which ones were ...
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How are the boundaries of a gene determined?
What statistical processes and methods are used by geneticists/molecular biologists to know where one gene starts and one ends?
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Can an adult without genetic lactase persistence still develop a tolerance for dairy foods?
While investigating the rise of adult lactose tolerance, I came across the news that China has been encouraging its citizens to drink more milk, even though most of the Asian population lacks the SNP ...
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How can you identify if a person is homozygous for a certain allele?
I've been thinking about starting a small private research project. In this project I need to find out whether a person is homozygous for a certain allele. The reason for this is that I'm really ...
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What are limiting factors for intron length?
For predicting genes from a sequenced genome, you need to set a maximum intron length. How long can introns get in animals? Is there some limit?
