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Systematic screening identified patients with an iron refractory iron deficiency anaemia (IRIDA) phenotype and genotype in iron-deficient children in the Indian subcontinent. Cases of moderate to severe microcytosis and anaemia with no obvious cause and normal C-reactive protein, HbA and tissue transglutaminase antibody levels (n = 550) were put on a trial of oral iron for 4 weeks. Sixty of these 550 cases (11%) were variably refractory to oral iron therapy (<10 g/l Hb rise) at 4-6 weeks and were subsequently evaluated for plasma iron, ferritin and hepcidin levels. The mean age of this cohort was 2.06 years. Low-normal to normal ferritin and normal to high hepcidin levels were noted in 25/60 (41.6%) and 47/60 (78.3%), respectively. An IRIDA phenotype was noted in 38.3% (23/60) based on standard criteria. TMPRSS6 gene sequencing in 20 cases with IRIDA phenotype revealed 9 potentially deleterious intronic and two benign exonic variations in 12/20 cases (60%). Of these, 4 intronic and both exonic variations were noted in multiple cases and are likely to act synergistically leading to an IRIDA phenotype. However, given that only 38% (23/60 cases) of cases with iron refractoriness had IRIDA phenotype, a balanced approach is needed and other causes for refractoriness should be investigated before genetic studies for TMPRSS6 are undertaken.

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Cardiac blood flow is a critical determinant of human health. However, definition of its genetic architecture is limited by the technical challenge of capturing dynamic flow volumes from cardiac imaging at scale. We present DeepFlow, a deep learning system to extract cardiac flow and volumes from phase contrast cardiac magnetic resonance imaging. A mixed linear model applied to 37,967 individuals from the UK Biobank reveals novel genome-wide significant associations across cardiac dynamic flow volumes including aortic forward velocity, total left ventricular stroke volume, forward left ventricular flow and aortic regurgitation fraction. Mendelian randomization using CAUSE reveals a causal role for aortic root size in aortic valve regurgitation. The most significant contributing variants (near ELN, FBN1 and ULK4) are implicated in connective tissue and blood pressure pathways. DeepFlow cardiac flow phenotyping at scale, combined with population-level genotyping data in the UK Biobank, reinforces the contribution of connective tissue genes, blood pressure and root size to aortic valve function in the general population.

Aim: To induce BCR-ABL gene silencing using CRISPR Cas13a. Background: CML is a clonal myeloproliferative disorder of pluripotent stem cells driven by a reciprocal translocation between chromosome 9 and 22, forming a BCR-ABL fusion gene. Tyrosine-kinase inhibitor drugs like imatinib are the mainstay of treatment and cases resistant to these drugs have a poor prognosis in the absence of a compatible stem-cell donor. However, with rapid advancements in gene-editing technologies, most studies are now focusing on developing a translational model targeting single-gene disorders with a prospective permanent cure. Objective: To explore the potential application of the RNA targeting CRISPR-Cas13a system for effective knockdown of BCR-ABL fusion transcript in a CML cell line, K562. Method: CRISPR Cas13a crRNA was designed specific to the chimeric BCR-ABL gene and the system was transfected as a two-plasmid system into a CML cell line, K562. The effects were enumerated by evaluating the expression levels of downstream genes dependent on the expression of the BCR-ABL gene. Also, next-generation sequencing was used to ascertain the effects of CRISPR on the gene. Results: The CRISPR system was successfully able to lower the expression of downstream genes [pCRKL and pCRK] dependent on the activated BCR-ABL kinase signal by up-to 4.3 folds. The viability of the CRISPR treated cells were also significantly lowered by 373.83-fold [p-value= 0.000891196]. The time-dependent kinetics also highlighted the significant in-vitro suppressive activity to last up to 8 weeks [p-value: 0.025]. As per the cDNA sequencing data from Oxford MinION next-generation sequencer, the CRISPR treated cells show 62.37% suspected cleaved reads. Conclusion: These preliminary results highlight an excellent potential application of RNA targeting CRISPRs in Haematological neoplasms like CML and should pave way for further research in this direction.