The exome is the part of the genome

Genome

In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....

 formed by exons, coding portions of gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s in the genome that are expressed

Gene expression

Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as ribosomal RNA , transfer RNA or small nuclear RNA genes, the product is a functional RNA...

, that is, provide the genetic blueprint used in the synthesis of proteins and other functional gene product

Gene product

A gene product is the biochemical material, either RNA or protein, resulting from expression of a gene. A measurement of the amount of gene product is sometimes used to infer how active a gene is. Abnormal amounts of gene product can be correlated with disease-causing alleles, such as the...

s. It is the most functionally relevant part of the genome, with regard to coding for proteins, and, therefore, it is most likely to contribute to the phenotype

Phenotype

A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...

 of an organism. The exome of the human genome

Human genome

The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs plus the small mitochondrial DNA. 22 of the 23 chromosomes are autosomal chromosome pairs, while the remaining pair is sex-determining...

 is estimated to comprise 1.5% of the total genome.

Some exome-based projects include the nonprofit Personal Genome Project

Personal Genome Project

The Personal Genome Project is a long term, large cohort study which aims to sequence and publicize the complete genomes and medical records of 100,000 volunteers, in order to enable research into personalized medicine. It was initiated by Harvard University's George Church and announced in...

 (PGP), the NIH-funded Exome Project, and the microarray

Microarray

A microarray is a multiplex lab-on-a-chip. It is a 2D array on a solid substrate that assays large amounts of biological material using high-throughput screening methods.Types of microarrays include:...

-based Nimblegen SeqCap EZ Exome from Roche Applied Science

Roche Applied Science

Roche Applied Science is producers of reagents and systems for life science research, with focus on DNA sequencing, microarrays, gene expression, and cell analysis. Important applications fields of the company´s products are Biotech R&D and Pharma R&D...

.