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Milewicz, D.

Publications and source records attributed to Milewicz, D..

2 recordsLinked to original sources

Genome-wide analysis yields new loci associating with aortic valve stenosis

Aortic valve stenosis (AS) is the most common valvular heart disease, characterized by a thickened and calcified valve causing left ventricular outflow obstruction. Severe AS is a significant cause of morbidity and mortality, affecting approximately 5% of those over 70 years of age1,2,3. Little is known about the genetics of AS, although recently a variant at the LPA locus4 and a rare MYH6 missense variant were found to associate with AS5. We report a large genome-wide association study (GWAS) with a follow-up in up to 7,307 AS cases and 801,073 controls. We identified two new AS loci, on chromosome 1p21 near PALMD (rs7543130; OR=1.20, P=1.2x10-22) and on chromosome 2q22 in TEX41 (rs1830321; OR=1.15, P=1.8x10-13). Rs7543130 also associates with bicuspid aortic valve (BAV) (OR=1.28, P=6.6x10-10) and aortic root diameter (P=1.30x10-8) and rs1830321 associates with BAV (OR=1.12, P=5.3x10-3 and coronary artery disease (CAD) (OR=1.05, P=9.3x10-5). These results indicate that AS is partly rooted in the same processes as cardiac development and atherosclerosis.

genetics

A mutation in the LMOD1 actin-binding domain segregating with disease in a large British family with thoracic aortic aneurysms and dissections

We describe a mutation in LMOD1, which predisposes individuals to thoracic aortic aneurysms and dissections in a large multi-generation British family. Exome variant profiles for the proband and two distantly related affected relatives were generated and a rare protein-altering, heterozygous variant was identified, present in all the exome-sequenced affected individuals. The allele c.1784T>C, p.(V595A) in LMOD1 is located in a known actin-binding WH2 domain and is carried by all living affected individuals in the family. LMOD1 was further assessed in a consecutive series of 98 UK TAAD patients and one further mutation was found, yielding an incidence of [~]2% in our study group. Assessment of LMOD1 in international TAAD cohorts discovered nine other missense variants of which three were classed as likely pathogenic.\n\nValidation of LMOD1 was undertaken using a zebrafish animal model. Knock-down of both lmod1a and lmod1b paralogs using morpholino oligonucleotides showed a reproducible abnormal phenotype involving the aortic arches under off-target controls. Injection of the human LMOD1 c.1784T>C, p.(V595A) mutation demonstrated a likely dominant negative effect and illustrated a loss of function cause.\n\nMutations found in the WH2 actin-binding domain of LMOD1 may delay actin polymerization and therefore compromise actin length, dynamics and interaction with myosin in the smooth muscle contraction pathway.

genetics