Skip to Content
Data Algorithms
book

Data Algorithms

by Mahmoud Parsian
July 2015
Intermediate to advanced
778 pages
17h 9m
English
O'Reilly Media, Inc.
Content preview from Data Algorithms

Chapter 21. Allelic Frequency

Allelic frequency analysis is a technique used to find the frequency of alleles for genomic data (especially for the germline data type). An allelic frequency is defined as “the percentage of a population of a species that carries a particular allele on a given chromosome locus.” In this chapter, we’ll develop a MapReduce solution to aggregate all genomic data for each desired key (composed of [chromosome, start-position, stop-position]), then apply Fisher’s Exact Test, a statistical test to determine if there are nonrandom associations between two groups of variables (these two groups of variables can be patient biosets, which will be discussed shortly). We will then analyze and plot the output of the MapReduce program. The input for allelic frequency calculation comes from VCF files generated by DNA sequencing pipelines. Typically each VCF record includes chromosome, start-position, stop-position, genome-reference, and two alleles (labeled allele1 and allele2—one from the mother and one from the father). This information will be sufficient for us to perform an allelic frequency analysis for two sets of data.

The main goal of this chapter is to present a MapReduce solution to allelic frequency calculation using Fisher’s Exact Test, comprising three MapReduce jobs.

To comprehend the importance and the impact of allelic frequency, you must first understand the meaning of mutations, migrations, and selections. For details on these concepts, see the ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

Data Algorithms with Spark

Data Algorithms with Spark

Mahmoud Parsian
Grokking Algorithms

Grokking Algorithms

Aditya Bhargava
Graph Algorithms

Graph Algorithms

Mark Needham, Amy E. Hodler

Publisher Resources

ISBN: 9781491906170Errata Page