Tag Archives: Tristan da Cunha

An update on the asthma exome

Here is a quick update on some genes of my recent asthma exome paper coming now from the 1 M  exome paper published yesterday as a preprint.

loss of function variants IL1RL1. https://rgc-mcps.regeneron.com/gene/IL1RL1, 12 May 2023

Also ClinVar shows that the IL33 receptor is not “essential” making anti IL33 receptor antibodies like etokimab, itepekimab, tozorakimab a safe therapy although not being effective in any LOF mutation carrier.

The most interesting thing in the preprint is in supplemental table 2 with the s-het values for 16,704 genes. From that table  I have selected  my favorite target  IL33 receptor together with TLR1, ALOX15, GSDMA, IL13 and IKZF3 ( BTNL2 could not be found in the list).

asthma exome  https://rgc-mcps.regeneron.com/gene/IL1RL1, 12 May 2023

IKZF3 would be dangerous to be touched (see my 2008 commentary) while in the 2022 exome paper I  also found  only protective variants in the 5′-UTR but not any LOF variant   – probably as IKZF3 is the only essential gene in the list.

So what’s next? I am still thinking how to reduce my exome set to the causal variants as half of the mutations are probably LD artefacts. And well, it would be super interesting to examine now two extreme inbred populations for their mutation spectrum,  loosing either asthma variants by healthy (Amish) or diseased founders (Tristan da Cunha). Unfortunately there is little hope that this will happen – current science is built more on competition than collaboration.


What did Sequana really find at Tristan da Cunha?

The Tristan da Cunha asthma study  was leading to patent US6087485A. The patent describes

highly significant linkage in the genome scan (p=0.0001 for history of asthma and p=0.0009 for methacholine challenge) … at D11S907, a marker on the short arm of chromosome 11.

D11S907 or  AFM109YA1 is a microsatellite marker located at 11p13 in a gene known as EHF (ETS homologous factor).  There should be 2 genes in close proximity of the marker: ASTH1I and ASTH1J.

ASTH1I and ASTH1J were detected by exon trapping. ASTH1I exons detected a 2.8 kb mRNA expressed at high levels in trachea and prostate, and at lower levels in lung and kidney …
ASTH1J exons detected a 6.0 kb mRNA expressed at high levels in the trachea, prostate and pancreas and at lower levels in colon, small intestine, lung and stomach.

The sequences of  table 2 in the patent are sufficient now to locate ASTH1I and ASTH1J. Continue reading What did Sequana really find at Tristan da Cunha?