Genomic testing increases the accuracy of EPDs across several traits quickly and at a relatively low cost. For several traits, adding genomics is like adding 15 to 25 progeny records to that animal’s EPDs. With so many different genomic tests offered, trying to determine which test to use can be a head-scratcher. This Down to the Genes article provides information to help choose the best genomic panels to use.
A couple of points to note before we dive into the details.
1. In order for genomic panels to add accuracy to ASA published EPDs, the genomic test needs to be completed with ASA (or another breed association in International Genetic Solutions) and the animal needs to have EPDs. The product returned to the member is the genomically-enhanced EPD. An animal must have an EPD in order for the genomic test to be useful.
2. Genomic testing will NEVER replace the need for recording performance data. Phenotypes will continue to be a vital part of genetic evaluation and predicting an animal’s genetic merit. Genomics allow younger/unproven animals to see a boost in accuracy of EPDs early in their lives, but high accuracy can only be obtained through progeny testing. Additionally, the predictive value of future genomic tests increases as there are more phenotypic and genomic records. If breeders stop sending in performance data, genomics will be less informative to the genetic evaluation.
3. An animal must first be placed “on file” in the ASA database before a member can order a genomics test. This does not mean the animal needs to be registered. “On file” means the animal is in the ASA database with an ASA number. There is no fee to put an animal on file and it is required with genomic testing because the animal’s ASA number becomes part of the unique ID connecting the genomic information to the genetic evaluation. Without a unique ASA number, the genomic results are harder to track and might not make it into the genetic evaluation. For stepby-step instruction on how to put an animal on file, check out the Profit Through Data blog.
Distinctions between panels: DNA marker volume/density: Currently, the ASA has three density panels for routine genomic testing. The GeneSeek® Genomic Profiler (GGP) ultralow density (uLD) has 33,000 DNA markers for $33. The GGP low density (GGPLD; called the 50K by GeneSeek) has 47,000 markers for $50. The high density (GGP-HD) has 150,000 markers for $90. Breeders should use higher density genomic tests in animals with larger genetic impact (current or potential). Because of the high impact AI sires and donor dams have, they are required to have a GGP-HD test completed. Natural service sires, or walking bulls, are a little cloudier. They should at least have the medium density chip (GGP-LD), but if they have a large impact in your herd, a higher density could be considered. Cows or replacement heifers could get by with the GGP-uLD unless additional traits are tested. If you are interested in testing the entire cow herd, contact ASA about the Cow Herd DNA Roundup, a program providing the GGP-LD test at a greatly reduced price.
GGP-LD and HD panels offer add-on content, meaning results for traits like coat color, horned/polled, and some genetic conditions can be pulled off the genomic panel at a reduced cost compared to running these DNA tests independent of a genomic panel (stand-alone). If these traits are of interest, breeders need to select either GGP-LD or HD.
All the genomic panels contain parentage markers so parentage is included with each genomic option. In order for an animal to be compared to their sire/dam, the sire and/or dam will need to have SNP parentage markers with ASA. If the parent has microsatellite (or STR) markers, ASA will not be able to compare to the microsatellite markers. If the parents had SNP parentage markers completed with another organization, the member will need to request the SNP parentage markers on the parents be sent to ASA from the original testing organization.