Genetic:Recombination map and Physical Map

1) Why are both recombination maps and physical maps important? What are the differences between them?

2) When does crossing over occur?

3) What kind of recombination frequency is diagnostic for linkage?

4) Why do we make test crosses for mapping with the double recessive line?

5) How do we measure ‘distance’ when we map?

Are distances relative or absolute?

1--recombination map is the linkage map it can only be constructed for loci that occur in two or more heritable forms

physical map can be made from direct DNA analysis both are important as we try to correlate for acurate test and result

2--Crossing over takes place at hotspot site where there is high degree of complementarity

3--If the genes were independent, using standard genetic techniques you would predict that your offspring would have the phenotypic ratio,this would help in linkage,

Linkage analysis can be used to diagnostics linkage

4--For detecting linkage we do double recessive lines

5--- linkage map unit (LMU) these are relative as it can vary with Frequency of crossover (and thus of recombination) can be affected by location (crossing over is repressed close to the centromere) and proximity to another corssover.

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Unknown Monday, December 23, 2013  No comment

DNA will replace hard drives

DNA should not be just a medium for genetic imprint for organism ,it can be used as a information storage unit,the advantage of DNA is it's abundance it's freely available

DNA has been storing information for millions of years passing from generation to generation with very low error rate.That gives DNA an advantage of keeping our data secure.Now we are in the age of information ,the age of big data,we need to store these data effectively and not only storage but we can retrieve and do the job to our need.

DNA vs Hard drive

What might be the constraint for DNA to be used as Storage device?

One  need to develop an interface that allows for quick storage, reading and error correction of DNA.  Then it will need to be perfected.
 
Computer storage is measured in many ways.

• Access time
• Write speed
• Read speed
• Longevity
• Capacity
• Power consumption
• Physical size
• Error rate
• Cost

In order to replace hard drives, it will need to have a a clear advantage in at least one area and be relatively close in most other areas.  Given that we don't have this capability at all, it will need to be created and iterated until it shows an advantage.  By the time this happens, I doubt we will be using hard drives anymore.
 
Flash memory has replaced hard drives in many applications - it exceeds hard drive technology in several aspects and it's in the ballpark in most others.  It is a mature technology that is very profitable and many companies are refining it.  As a semiconductor-based technology it can benefit from improvements in other areas of semiconductor research.  I predict that it, or another technology, will displace hard drives in the majority of applications before DNA storage is commercially available

What are the other aspects of DNA that make it a perfect choice for being used as a storage device?

 Storage density of DNA is at least a thousand times greater than that of any storage device so far humans have created

For example the cheap storage media such as the magnetic tapes used to data archiving becomes fragile and gets degraded.

Another aspect is the format,some format that was/were the standard of late 70's now does't exist so it's really difficult for the data of that period to be viewed in today's software and store it effectively .

Biggest advantage of DNA is it's stability it is the most sturdy molecule that was ever created on this earth it can remain for millions of years without getting degraded .

So I hope like other fancy technology that were just a thought came into our life I hope to see this DNA storage technology to be seen soon and used in our daily life.

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Unknown Wednesday, November 27, 2013  No comment