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33

It is true that the Y chromosome is shorter than the X chromosome and that there are more genes on the X chromosome. Do men have fewer genes? One could (mis)understand three things in the expression "number of genes". Number of gene copies (see Copy Number Variation) Number of genes Number of alleles Thanks to @GerardoFurtado for correcting my ...


33

It is highly unlikely that there exist any protein that is made from completely identical nucleotide sequences across the entire human population. There will certainly be regions within a gene that are highly conserved, but there is little evolutionary pressure to conserve an entire gene's nucleotide sequence across the population. This is in part due to ...


23

Humans have many variants There is variation. The project I use to help understand this natural variation is gnomAD. Using VarMap and a slightly out of date gnomAD file, I counted 16007805 protein-coding variants across the human genome. This number will only go up over time. Indeed, the 1000 Genome project found that on average each person has between 250-...


11

...would then be his offspring at risk? Why? No. Generally speaking, fathers do not pass on their mtDNA (Mitochondrial DNA). Why? Because the mitochondria present in oocytes (egg cell) is the mother's, as every oocyte directly inherits the mother's mitochondria when they are made in the reproductive organs. The mitochondria that the sperm from the father ...


11

This Nature paper from 2004, by Jane Grimwood et al. goes at least a long way towards giving an answer to the question of the OP. In short: there were inordinately many duplications, especially during an event 30-40 million years ago, as well as during a much more recent event. These duplications are, uncharacteristically, predominantly intra-chromosomal ...


11

This image from the Kahn Academy article 'Overview of transcription' might help: Essentially, the sense/coding strand of the DNA encodes the sequence that is transcribed. The RNA polymerase binds to the antisense/template strand, for which the code is indeed TAC, but when it then transcribes this strand it is again complemented, giving us the AUG that is ...


9

None of the highlighted regions in your figure, is a gene. A gene is a section of DNA which gives rise to a product. Basically, a gene has an orientation (5'→ 3') i.e. it is essentially a single stranded region. However, the strand that mechanistically contributes to RNA synthesis (template) has the reverse-complementary sequence of the gene (in other words, ...


8

Take a look at this schematic of a mature mRNA. [source] The coding region (ie the part that is translated) is between the start and stop codons, but the 5' and 3' untranslated regions (UTRs) are also transcribed by RNA polymerase; these are part of the first and last exons, respectively. The transcription start site is labelled right in front of the 5' ...


8

The picture can be a bit misleading because it represents 22 autosomes (autosome = non-sexual chromosome) while there are 22 pairs of autosomes (so the homologous chromosome is not represented). And it represents the whole pair of sexual chromosomes (the individual is a male). homologous chromosome For each autosome represented, there is another one which ...


8

Since I have used more than 1 image in my answer; with numbers starting from 1; I'll call your provided figure as figure-0 What is shown in following picture? Though the image showing many things; in overall it is an image of a set of chromosomes; seemingly almost certainly from human. The chromosomes has been stained with a banding method (though I'm ...


8

A few words on genomic prediction No complex trait is 100% heritable, hence no prediction based entirely on DNA would ever be perfect. With that said, predictive genomics is progressing at a quite amazing rate right now. So while predictions can be nowhere near perfect, it is getting possible to make DNA predictions that correlate substantially with observed ...


8

At the whole-gene level, there is likely no absolute conservation of any human protein-coding gene at the population level, though there might be complete conservation between individuals. Keep in mind that most human genes are on the order of tens of thousands of base pairs long, and only a portion of that length encodes functional motifs. There are, ...


8

It depends on the regions of sequence homology between the two chromosomes. Crossing over occurs through pairing of homologous regions. If there's a substantial stretch of chromosome without a matching homologous region on its pair, that non-homologous region should loop out and not be involved in crossing over. Crossovers will occur only in paired ...


7

I would suggest searching the name in any trusted genetics database such as NCBI's GenBank (http://www.ncbi.nlm.nih.gov/genbank/). You can just Google search it, but it may take a little longer to find useful information that way. I hope this helps and good luck with your research, CDB


7

Alleles are basically subtypes of a gene. At the time of Mendel, the molecular nature of inheritance was not known so the original definition of gene refers to "some" inheritable molecular entity inside the organism that is responsible for a trait. Alleles are different "flavours" of a given gene. For example there is a gene for flower colour, there can be ...


7

You may or may not consider this an actual answer to your entire question, but it's interesting nonetheless. A physicist friend of mine did some work recently modelling the quantum dynamics of photosynthetic complexes, and their coupling constants for passing energy throughout the photosystem. His results showed that, (and I believe this is in agreement ...


7

"Intergenic" is, well, an embarrassment, though it can be hard to avoid. Intergenic means, literally, between genes. Genes are, as you'd expect, genetically defined as regions of the chromosome with some genetic role. Between genes, we have, well, junk, spam, without meaning or significance, since otherwise, it would be a gene. In the 1990s ...


6

Most promoter elements are not a part of the mRNA sequence. They are upstream (towards 5') of the transcription start site. However, a certain class of promoters called downstream promoter elements (DPE) can overlap with the geneic region. These elements have been reported to lie at 29-33bp upstream of the transcription start site and widely employed, in ...


6

Fur, wool, and hair are all made of keratins. To the best of my knowledge wool and fur are separated arbitrarily, based on the properties of the fibres. This arbitrary division allows rabbits to have fur but selective breeding has produced angora rabbits, which have wool. The opposite should be possible, with time you could breed a sheep that has fur. ...


6

WES, almost certainly. First of all, the vast majority of phenotype-causing variants are found in exons. For most analyses that are looking into disease causing mutations, WGS is pointless. It only makes your analysis harder and doesn't actually add anything useful. If you know you're interested in CNVs, that's different. CNV detection is hard in general but ...


6

More than two alternative forms (alleles)of a gene in a population occupying the same locus on a chromosome or its homologue is known as multiple alleles. Multiple alleles arise due to mutations of gene.A gene can mutate several times by producing a series of alternative expressions.Different alleles in a series show dominant-recessive relation or may show ...


6

There is no single answer, because networks (or graphs, as they are called in discrete mathematics) are flexible tools that can be used to model all sorts of relationships between genes, transcripts, proteins, or other entities in biology. (And networks are useful models in many other disciplines too, like sociology.) Depending on the type of network you're ...


5

So, the very first map of the human genome was of a few pooled samples with a single nucleotide called at each position. This is basically okay, though, because humans are 99.9 (with possibly a few more 9s) % similar to one another. So you can get a lot of broadly-applicable information out of a single individual's DNA. Further genome-mapping efforts ...


5

TL;DR: Ubiquitin. Occasional occurrence of paternal inheritance of mtDNA has been suggested in mammals including humans. Clearly, spermatozoa have mitochondria; they make the energy needed for motility. Paternal mitochondrial DNA (mtDNA) does enter oocytes. It is a persisting fallacy that only maternal mtDNA is present in humans because only oocyte ...


5

TL;DR: Chymosin is similar to pepsin and I couldn't find any evidence of functional/expressed chymosin gene in human genome. It seems like a common misconception that chymosin is functional in humans. Already in 1940s it has been shown that rennin (aka chymosin) is absent from "gastric juice" in adult humans. Genetically there is only pseudo-gene for ...


5

Was getting long in the comments. In light of your comments, you might be interested in Gene-set enrichment analysis (GSEA). You can do a GSEA using your set, the other one coming from reference databases such as MSigDB (see here). You can categorize your list by gene families using this technique for example. You can get an idea of what cellular process ...


5

Physical and genetic interactions are described in the help wiki, accessed via the top menu bar on the page you linked to. Physical interactions refer to experiments where the gene product (protein) has been shown to physically interact with another protein, such as by co-immunoprecipitation, fluorescent staining, yeast two-hybrid system, etc. Genetic ...


5

You mix up translation and transcription. Transcription creates mRNA from DNA template. Transcription also includes splicing, that is excision of introns so that mature mRNA contains only exons. In your example it goes like that: DNA (chromosome): ---A----B--...--Dstop---E--- premature mRNA: A----B---...---Dstop--E---polyA mature mRNA: AB..DstopE-polyA ...


5

Little harm comes from ABO incompatibility (that would have been a major problem with reproduction.) Rh incompatibility is more dangerous, though. If a fetus is Rh+ and the mother is Rh-, when there is mixing of maternal-fetal blood (at birth, but sometimes before that), the mother will form antibodies to the blood cell surface antigen. It doesn't usually ...


5

So the term allele is a broad one, and simply refers to the different versions of any piece of DNA in circulation in the gene pool - it doesn't need to refer to a gene. I can talk about the alleles at a random place in the genome. But if we proceed with your question and ask - 'do nonsense mutations within coding genes also lead to the creation of different ...


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