Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics.

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What exactly is meant by the expression “differentially expressed”?

As far as I've seen, this expression is almost always used in relation to gene expression profiling. Unfortunately, I have no background in this area. Can someone please explain this in layman terms?
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0answers
45 views

Determine which gene is in the middle complementation [duplicate]

Possible Duplicate: Crossing mutant strains on minimal media problem I'm studying this problem for my genetics final: My Attempt: The answer for part B is met2 and the answer for part C ...
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0answers
121 views

How to find Dmax (genetics problem) [closed]

My attempt: I'm not sure this is right but this is what i did. I found the allele frequencies to be: A=0.4 B-0.3 a=0.1 b=0.2 I think to find Dmax I just multiply the two alleles with the larges ...
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1answer
108 views

Why can't we breed watermelons without any remaining seeds in the flesh?

Watermelon is just starting to come in season in the northeastern U.S., and having a seedless watermelon is convenient. The only downside is, the "seedless" almost always still have the immature, ...
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1answer
838 views

The genetic and physiological origins of laughter?

This Wikipedia article defines laughter in many terms, such as... "a visual expression of happiness, or an inward feeling of joy" and "a part of human behavior regulated by the brain, ...
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1answer
224 views

Finding DNA from Amino Acid sequence problem

My attempt: First I took the single letter AA codes and made them amino acids. So, the first one is Trp which is 5'-UGG-3'. From this I got the DNA sequence 3'-CCA-5'. However, the correct ...
12
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1answer
208 views

Have any mutations or genetic loci been associated with exceptional longevity in humans?

Individuals that avoid age-related diseases into later life are known as 'exceptional survivors', and have increased longevity compared to their 'controls' (those that were born at a similar time, yet ...
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4answers
1k views

Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them? ...
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1answer
538 views

Do trees age on a microscopic level?

Most animals age via at least two mechinisms: at a "macroscopic" level, basically wear and tear to the point where (on evolutionary time scales) it's more genetically advantageous to optimize for ...
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1answer
48 views

Which functional annotations could be useful?

Analyzing a genome, for a generic gene, which functional annotations (e.g from Gene Ontology) can help understanding its meaning/function or, at least, provide helpful informations? Annotations of ...
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3answers
211 views

Genetic effects on personality

It is said that genes are partly responsible for the choices we make in our life; our genes help to create our environment, and then that environment can influence our personality. So, beside genes, ...
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4answers
7k views

How many genes do we share with our mother?

Somewhere I have read we share more than 99% of our genes with every other other person and 98% of our genes with chimpanzees. What does this mean? Don't we share 50% of our genes with our mother and ...
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205 views

Linkage and LD: quantitative or qualitative?

My understanding is that the concept "genetic linkage" can be expressed in quantitative form, like: A predisposing gene X was found in close genetic linkage to Y. ...
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1answer
2k views

On the genetics behind caste marriages

I am in India where it is typically a custom to marry within one's caste. Basically the caste system originated with roots in people's professions - Each of priests, carpenters, troupers, etc had a ...
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4answers
1k views

What's the aim of genetically modifying of foods/organisms?

On news, articles etc. experts talking about Genetically Modified Foods and Organisms often mentions about their disadvantages like, their potential to harm human health allergies may become more ...
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2answers
1k views

Altering the human genome

I recently had a conversation with a rather unusual gentleman who was, let's say, more than a little partial to conspiracy theories. He has this idea that governments are lowering "nanowires" from ...
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1answer
196 views

What is the difference between copy number changes with and without allelic imbalance?

I require some clarification on copy number aberrations (structural gain and loss in chromosomes). From what I understand, gain/loss per se can be divided into two types. Consider two alleles, A and ...
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2answers
283 views

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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5answers
7k views

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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1answer
283 views

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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1answer
9k views

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 ...
5
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1answer
570 views

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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2answers
4k views

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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3answers
1k views

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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3answers
104 views

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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3answers
149 views

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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2answers
5k views

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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4answers
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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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2answers
353 views

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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1answer
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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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1answer
78 views

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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1answer
254 views

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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2answers
121 views

Is it possible to trace of the ancestry of a person by only using his/her genetic information?

Is it possible to trace the descent of a person only using his/her genome sequence?
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2answers
2k views

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 ...
12
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1answer
309 views

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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227 views

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 ...
9
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1answer
91 views

Which patterns do I have to avoid when modifying the 3'-UTR?

I want to change a pre-miRNA sequence (in my case the pre-miRNA is encoding in a 3'UTR of a gene) and then put it in a lentivirus to see if it is still processed. After modification (permutation of ...
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4answers
6k views

Why 22 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 22 ...
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1answer
1k views

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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99 views

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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3answers
2k views

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 ...
10
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1answer
394 views

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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6answers
945 views

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 ...
14
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2answers
340 views

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?
21
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2answers
453 views

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 ...
7
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1answer
784 views

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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1answer
622 views

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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4answers
533 views

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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2answers
328 views

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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1answer
174 views

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 ...