Assertion Supported AI assessment confidence: 95% certainty 5/5 debate potential 2/5

Church: Double-null CCR5 mutations increase susceptibility to West Nile virus

George Church · a16z Podcast | What's in the Water at the George Church Lab? · Apr 1, 2019 · at 4:39

Harvard geneticist George Church discusses potential health trade-offs and side effects of CCR5 gene editing with Andreessen Horowitz partner Jorge Conde.

0:00 / 0:09exact quote · 9.2s

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“That is correct. So there's a risk for almost every preventative and therapy, and this is the risk in this case, in most populations that's considered a smaller medical risk.”

quote is from the automated transcript, cleaned for reading: filler sounds and stutters are removed, nothing is rephrased. names can be misheard (the analysis reads context, assessments check outside sources). how →

The claim, plainly

Geneticist George Church confirms that individuals with double-null CCR5 gene deletions face an increased predisposition to West Nile virus infection.

a quote alone can be ambiguous, so this restates it with the references and context of the conversation around it resolved. AI-written; the tape below the player is the source.

Assessment

Peer-reviewed genetic and epidemiological research consistently confirms that individuals homozygous for CCR5 loss-of-function variants (CCR5-delta 32 double nulls) face a significantly increased risk of symptomatic and severe neuroinvasive West Nile virus (WNV) disease. Landmark studies including Glass et al. (2006) and Lim et al. (2008) demonstrated a 4- to 9-fold increased risk of symptomatic WNV infection and elevated mortality in homozygous carriers. Subsequent large-scale analyses (Lim et al., 2010; Cahill et al., 2018) established that while CCR5 deficiency does not alter mosquito transmission/acquisition rates, it impairs neuroprotective leukocyte trafficking to the central nervous system, directly predisposing infected individuals to severe clinical manifestations and encephalitis.

Glass et al. (2006, JEM) found CCR5-delta 32 homozygosity strongly associated with symptomatic WNV (OR = 4.4 to 9.1) and fatal outcome (OR = 13.2).
Lim et al. (2008, JID) meta-analysis across four epidemic cohorts confirmed CCR5 deficiency as a strong risk factor for symptomatic WNV infection (OR ~4.2).
Lim et al. (2010, JID) demonstrated that while initial viral acquisition is unaffected, CCR5 deficiency substantially elevates the risk of progression to severe clinical disease.
Comprehensive reviews through 2024 confirm the biological mechanism: CCR5 mediates critical leukocyte recruitment to clear WNV from the CNS, leaving double-null carriers susceptible to severe neuroinvasive disease.

Checked against

[1] a16z.com [2] nih.gov [3] eurekalert.org [4] nih.gov [5] oup.com [6] natap.org [7] nih.gov [8] mdpi.com

"CCR5" "West Nile virus" meta-analysis susceptibility OR neuroinvasive CCR5 delta 32 West Nile virus susceptibility predisposition literature George Church CCR5 West Nile virus a16z podcast CCR5 delta32 homozygous West Nile virus risk infection

assessed as of 2026-08-27

This assessment is an AI reading of a public statement, made against the cited references with the confidence shown. It can be wrong. The quote, the tape and the references are all on this page; if something is off, use report an error below. full disclaimer →

Mentioned

CCR-V West Nile

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