The human genome contains approximately \(10^{6}\) copies of an \(A l u\) sequence, one of the best-studied classes of short interspersed elements (SINEs), per haploid genome. Individual Alus share a 282 -nucleotide consensus sequence followed by a 3 '-adeninerich tail region. Given that there are approximately \(3 \times 10^{9}\) bp per human haploid genome, about how many base pairs are spaced between each Alu sequence?

Short Answer

Expert verified
Answer: The average distance between each Alu sequence in the human genome is approximately 3000 base pairs.

Step by step solution

01

Write down the given information

The human genome has approximately \(3 \times 10^9\) bp per haploid genome and contains \(10^6\) copies of Alu sequences per haploid genome.
02

Calculate the distance between Alu sequences

To find the average distance between each Alu sequence, divide the total number of base pairs by the number of Alu sequences: \(\text{Average distance} = \frac{\text{Total base pairs}}{\text{Number of Alu sequences}}\)
03

Substitute the values and solve

Now, substitute the given values of base pairs and Alu sequences into the formula: \(\text{Average distance} = \frac{3 \times 10^9 \ \text{bp}}{10^6 \ \text{Alu sequences}}\) Divide the values: \(\text{Average distance} = \frac{3 \times 10^9}{10^6}= 3000 \ \text{bp}\)
04

Present the result

The average distance between each Alu sequence in the human genome is approximately 3000 base pairs.

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Most popular questions from this chapter

Provide a comprehensive definition of heterochromatin, and list as many examples as you can.

Mammals contain a diploid genome consisting of at least \(10^{9}\) bp. If this amount of DNA is present as chromatin fibers, where each group of 200 bp of DNA is combined with nine histones into a nucleosome and each group of six nucleosomes is combined into a solenoid, achieving a final packing ratio of \(50,\) determine: (a) the total number of nucleosomes in all fibers. (b) the total number of histone molecules combined with DNA in the diploid genome. (c) the combined length of all fibers.

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