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Newbie question: For few years I have seen news like "Whole-genome sequencing" is now under $1000 etc. I believed that this means all the base pairs of all chromatids in a single cell are identified and stored in a digital format in the original sequence. Just checked this Wikipedia article as well, which seem to align with my understanding. Today I saw many news articles saying that Y-chromosome was fully sequenced for the first time. For examplethisarticle, which also mention that other chromosomes were fully sequenced only early this year. What am I missing? Perhaps Whole is not whole?

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Final answer:

Whole-genome sequencing refers to determining the complete DNA sequence of an organism's entire genome, though it can also be used in a more limited context. Whole-exome sequencing is a lower-cost alternative that focuses on protein-coding regions of the DNA.

Step-by-step explanation:

The term "whole-genome sequencing" refers to the process of determining the complete DNA sequence of an organism's entire genome. However, it's important to note that the term "whole genome" can sometimes be used in a more limited context. For example, in the case of the Y-chromosome sequencing mentioned in the news article you saw, "whole-genome" refers specifically to the sequencing of the Y-chromosome rather than the entire genome of the cell. Whole-exome sequencing, on the other hand, is a lower-cost alternative to whole genome sequencing that focuses only on the protein-coding regions of the DNA, known as exons. This approach can still provide valuable genetic information and is often used when studying diseases with known genetic causes. So, while whole-genome sequencing can indeed refer to the sequencing of the entire genome, it can also be used in a more specific context to refer to the sequencing of a particular chromosome or a subset of the genome.

The term whole-genome sequencing generally refers to the process of determining the complete DNA sequence of an organism's genome at a single time. This includes all the DNA sequences of an organism, encompassing both the coding regions (exons) and non-coding regions (introns and non-coding RNAs). However, certain highly repetitive or complex regions might have been more challenging to sequence in the past, leading to gaps in the sequence. Recently, advancements in sequencing technology have now allowed previously unresolved regions like the Y-chromosome to be fully sequenced. It is crucial to distinguish between whole-genome sequencing and whole-exome sequencing. The latter is more cost-effective as it only targets the exons or coding regions, which represent a small fraction of the entire genome. For instance, through whole-exome sequencing, a boy with mysterious intestinal abscesses was diagnosed with a defect in the apoptosis pathway, showing how this approach can pinpoint genetic diseases. Rapid progress in sequencing technology has made genome sequencing more accessible. Now it is possible to sequence a human genome in a significantly reduced timeframe and at a lower cost than in previous years. As a result, medical professionals can use genomic information to tailor treatments to individual genetic profiles, potentially revolutionizing personalized medicine.

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