Dissection of pleiotropic effects of missense mutations, scarcely investigated in inherited diseases, is fundamental to understanding genotype-phenotype relationships. Missense mutations might impair mRNA processing in addition to protein properties. As a model for haemophilia A (HA) we investigated the highly prevalent F8 p.R2016W/c.6046c>t (exon 19) mutation. In expression studies exploiting lentiviral vectors, we demonstrated that the aminoacid change impairs both secretion (FVIII:Ag 11.0+/-0.4% of wild-type) and activity (FVIII:C 6.0+/-2.9%). Investigations in patients' ectopic F8 mRNA and with minigenes showed that the corresponding nucleotide change also decreases correct splicing to 70+/-5%, which is predicted to lower further FVIII:C (4.2+/-2%), consistently with FVIII:C levels observed in patients (1-5%). Masking the mutated exon 19 region by antisense U7snRNA supported the presence of a splicing regulatory element, potentially affected by several HA-causing missense mutations. Among these, the c.6037g>a (p.G2013R) reduced exon inclusion to 41±3% and the c.6053a>g (p.E2018G) to 28+/-2%, similarly to a variant affecting the 5' splice site (c.6113a>g, p.N2038S, 26+/-2%), which displayed normal protein features upon recombinant expression. The p.G2013R remarkably reduced both FVIII:Ag (7.0+/-0.9%) and FVIII:C (8.4+/-0.8%), while the p.E2018G produced a dysfunctional molecule (FVIII:Ag, 69.0+/-18.1%; FVIII:C, 19.4+/-2.3%). In conclusion, differentially altered mRNA and protein patterns produce a gradient of residual FVIII:C, and clarify genotype-phenotype relationships. The integrated approach details pathogenic mechanisms that, only in combination, account for symptomatic HA and thus determine the HA mutation profile. Overall data provide a clear example of interplay between mRNA and protein mechanisms of disease that certainly operate in shaping many other inherited disorders.
Pharmacology, Toxicology and Pharmaceutical Science
1
3%
Nursing and Health Professions
1
3%
Other
0
0%
Unknown
11
37%
Attention Score in Context
Attention Score in Context
This research output has an Altmetric Attention Score of 2. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 26 February 2018.
All research outputs
#17,537,019
of 27,788,586 outputs
Outputs from Haematologica
#3,543
of 4,895 outputs
Outputs of similar age
#255,195
of 454,369 outputs
Outputs of similar age from Haematologica
#52
of 88 outputs
Altmetric has tracked 27,788,586 research outputs across all sources so far. This one is in the 36th percentile – i.e., 36% of other outputs scored the same or lower than it.
So far Altmetric has tracked 4,895 research outputs from this source. They typically receive more attention than average, with a mean Attention Score of 8.7. This one is in the 26th percentile – i.e., 26% of its peers scored the same or lower than it.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 454,369 tracked outputs that were published within six weeks on either side of this one in any source. This one is in the 42nd percentile – i.e., 42% of its contemporaries scored the same or lower than it.
We're also able to compare this research output to 88 others from the same source and published within six weeks on either side of this one. This one is in the 40th percentile – i.e., 40% of its contemporaries scored the same or lower than it.
