23andMe Investor Presentation Deck
The Vast Majority of GWAS Discoveries Can
be Made Without Large-scale Sequencing
Nearby genetic variants are correlated with each other. Knowing
the variant in one position allows nearby variants to be inferred.
E.g. Fill in the blanks:
The q***k brown f*x jumps ov*r the **zy dog.
The same principle applies in genetics. The process of filling in
the gaps is known as 'genotype imputation'.
●
We type ~650,000 SNPs using our genotyping array, which
allows accurate imputation for >35m SNPs in the genome.
Genotype imputation is much more cost effective than large-
scale sequencing.
• Whole-genome sequencing -$1000/sample.
Exome sequencing ~$400 / sample.
Imputation < $0.01/ sample
We do deploy sequencing in situations where there is a clear
benefit over and above imputation (e.g. rare disease).
Genotyped Samples
1 1 2 2
0 1 2 2
1 2 1 1
2 2 2 2 121
111122
022 20:
2 2
1
1 1 0
1
0
-logp-value
20
15
in
O
20-
15
2
176.3
0
1
2 0
2
2
Un
1
0
88%
176.4
Reference Genomes
1100
176.5
611
2011077
rs1906265
Imputation Process
1212121201127120
12121?1701077170
1717171711177170
6090 %00
Doo
0101
110
01
170?0?0?1112?170
017070711177170
176.6
176.7
Position on chr5 (Mb)
176.8
Copyright © 2022 23and Me, Inc.
176.9
2
Imputed Samples
1
1 102 2001
012 201
1 20110120
2 2 2 2121
1101 101 22
022 2021
1101
2 2 1
1 100 0
177
2
2
0
23andMe
2 0
0
2
2 1
2
1
0
Before
imputation
After
imputation
57View entire presentation