由於構成生物基因體的核苷酸數目龐大，且定序技術無法一次讀取所有基因體，故採取將基因體切割成較小的基因片段(Reads)，並解讀之。基因組裝採用基因片段堆疊的方式，運用電腦程式拼湊堆疊的基因片段，重建原本的基因序列。近年來生物基因體紛紛被生物資訊學家們透過定序及組裝的方式找出，在文獻中，已有許多學者探討如何衡量生物基因體的長度，並研發了不同的分析軟體進行組裝。在本文中，主要探討以基因片段(Reads)堆疊的資料來估計其原本序列的長度。由於欲了解所提出估計方法是否能估計到真實序列的長度，故採用已知序列長度的物種，以序列比對(read mapping)方式獲得資料進行研究，並應用生態統計領域的樣本涵蓋率(sample coverage)以估計序列之長度。本文以實例分析，了解估計的準確性，並進一步探討需多少數量的基因片段，以期能估計到預期的鹼基對個數。

The DNA sequencing technology cannot read whole genomes in one go due to the huge number of the nucleotide for the genomes and the limitation of the DNA sequencing technology. The DNA is broken into millions of random fragments that are called “reads” by a DNA sequencing machine, and the base calling is used for assigning bases. A computer program pieces together the many overlapping reads and reconstructs the original sequence. Recently, there are more and more species which genomes are sequenced by the researcher of the bioinformation. How to estimate the length of the DNA sequence and the associated implementation have been introduced by many scholars in the literatures. In this article, the estimation for the length of the DNA sequence is based on the overlapping reads data, and the sample coverage method is applied in the proposed method. In order to understand whether the proposed method estimates the correct value or not, we use the known DNA sequence and the method of the read mapping to obtain the overlapping reads data. Through the real example study, the accuracy of the proposed method is discussed. Furthermore, how many the number of the reads is requisite to obtain the pre-specified accuracy.

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