21 CFR § 528.2000 - Deletion of exon 7 of CD163 gene in domestic pigs.

---
identifier: "/us/cfr/t21/s528.2000"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 528.2000 - Deletion of exon 7 of CD163 gene in domestic pigs."
title_number: 21
title_name: "Food and Drugs"
section_number: "528.2000"
section_name: "Deletion of exon 7 of CD163 gene in domestic pigs."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "E"
subchapter_name: "ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS"
part_number: "528"
part_name: "INTENTIONAL GENOMIC ALTERATIONS IN ANIMALS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 360b."
regulatory_source: "74 FR 6823, Feb. 11, 2009, unless otherwise noted."
cfr_part: "528"
---


# 528.2000 Deletion of exon 7 of CD163 gene in domestic pigs.

(a) *Specifications.* Deletion of one (heterozygous) or two (homozygous) copies of exon 7 of *CD163* gene1(abbreviated CD163ΔE7) in domestic pigs (*Sus scrofa domesticus*).

(b) *Sponsor.* See No. 086205 in § 510.600(c) of this chapter.

(c) *Conditions of use*—(1) *Intended use.* Deletion of exon 7 of the *CD163* gene in domestic pigs (*Sus scrofa domesticus)* is intended to confer resistance to porcine reproductive and respiratory syndrome virus (PRRSV) in homozygous pigs. Pigs carrying one or two copies of CD163*D*<sub>E7</sub>, and their offspring, are intended for breeding or to be used as sources of food.

[90 FR 40970, Aug. 22, 2025]