On the last chart I finally understood the sense of this technique. Thank you very much for this video :) A few more moving animations would have been nice, but this was also fine :) Good job!
I understand how the control fragments bind to the control probes since most genes are mapped on thew microarray but how does the test strand (cancer) bind to the probe? how does the DNA strand from a cancer cell find a match? the mutation could be in any nucleotide(s) or are there probes for the common mutation?
+msabri1 The oligos on the microarray are spotted in respect to normal cell's genome sequence. The normal cells would therefore synthesize the mRNAs and corresponding cDNAs through RT PCR would bind to their complementary strands on the microarray. The cancerous cells may produce normal mRNAs for some sequences which will hybridise to their complementary strands and mutated mRNAs for others which wont hybridise. Thus, A red colour on a feature means no cDNA from normal cells hybridised on it, only cancerous cells produced corresponding mRNAs and thereafter their cDNA probes. A green colour would mean only normal cells produce mRNAs for the corresponding gene and no expression occurs in the cancer cells for that gene sequence. A yellow spot means both cancer and normal cells equally express the gene sequence and therefore cDNAs from both of them hybridised on the feature and gave a mixed colour.
So are you saying that a unique microarray chip will be manufactured for each time one is used, and that it will be based on the test subjects own cellular mRNA?
Yehs, exactly ! Microarray chips are not reusable. Secondly, they are based on common coverage. For instance, a gene array for yeast is based on the gene sequences of Saccharomyces cerevisiae , which is the most common species. It can be used for the detection of transcripts of other species too.
to add; each micro array chip is manufactured based on the suspected abnormality or cancer type, with sequences of the known mutations involved with the suspected cancer type being part of the micro array chip or grid. In this way the mutant cDNA in the test cell(s) could hybridize to its complement probes in a specific feature and produce red color. The intensity of the red color is proportional to the extent of the mutation undergone in the cell
Is there a chance for a smaller or larger DNA to attach via a partial match to the feature? Like a smaller one hybrizes in the middle, and a larger on is dangling? What happens if it does this?
Actually, this is an RNA microarray or expression microarray, not a DNA/genomic microarray. The whole concept is wrong. You can only analyzed the DNA which is transcribed.
The best explanation for microarry on UA-cam
I love the simplicity and traditional genetics design. Very nicely done! :)
this was fantastically explained, thank you very much
On the last chart I finally understood the sense of this technique.
Thank you very much for this video :)
A few more moving animations would have been nice, but this was also fine :)
Good job!
The sniffing, I can't xD but I continue anyways..thanks for the video
Take care on Health.... Must be highly Prioritized...
Thank you so much!! Amazingly explained
Thank you! You've just saved my life
beautifully explained ! thank you so much !
Demonstration Very Nicely done... So Good...
Thank you. It's very brief and nice!
So helpful! Thanks!
this is beautiful and well explained. regards.
Thank you very much, this was very helpful ! :)
I understand how the control fragments bind to the control probes since most genes are mapped on thew microarray but how does the test strand (cancer) bind to the probe?
how does the DNA strand from a cancer cell find a match? the mutation could be in any nucleotide(s)
or are there probes for the common mutation?
+msabri1 The oligos on the microarray are spotted in respect to normal cell's genome sequence. The normal cells would therefore synthesize the mRNAs and corresponding cDNAs through RT PCR would bind to their complementary strands on the microarray. The cancerous cells may produce normal mRNAs for some sequences which will hybridise to their complementary strands and mutated mRNAs for others which wont hybridise. Thus, A red colour on a feature means no cDNA from normal cells hybridised on it, only cancerous cells produced corresponding mRNAs and thereafter their cDNA probes. A green colour would mean only normal cells produce mRNAs for the corresponding gene and no expression occurs in the cancer cells for that gene sequence. A yellow spot means both cancer and normal cells equally express the gene sequence and therefore cDNAs from both of them hybridised on the feature and gave a mixed colour.
So are you saying that a unique microarray chip will be manufactured for each time one is used, and that it will be based on the test subjects own cellular mRNA?
Yehs, exactly ! Microarray chips are not reusable.
Secondly, they are based on common coverage. For instance, a gene array for yeast is based on the gene sequences of Saccharomyces cerevisiae , which is the most common species. It can be used for the detection of transcripts of other species too.
Great answer, I understand it better now. Thank you very much.
to add; each micro array chip is manufactured based on the suspected abnormality or cancer type, with sequences of the known mutations involved with the suspected cancer type being part of the micro array chip or grid. In this way the mutant cDNA in the test cell(s) could hybridize to its complement probes in a specific feature and produce red color. The intensity of the red color is proportional to the extent of the mutation undergone in the cell
THANK YOU!
Is there a chance for a smaller or larger DNA to attach via a partial match to the feature? Like a smaller one hybrizes in the middle, and a larger on is dangling?
What happens if it does this?
+rasmasyean Only very strong and specific bound probes remain after stringent washing with buffer. However some error chances remain.
thanks alot
Who's watching this in 2021, the era of 'covid vaccines'?
Thats funny to hear the narrator having the stuffy nose XD
how much this process take?
Actually, this is an RNA microarray or expression microarray, not a DNA/genomic microarray. The whole concept is wrong. You can only analyzed the DNA which is transcribed.