Genome Sequences of 10 SARS-CoV-2 Viral Strains Obtained by Nanopore Sequencing of Nasopharyngeal Swabs in Malta.

The genome sequences of 10 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains from Sliema, Malta, were obtained by Nanopore sequencing using the amplicon sequencing approach developed by the Artic Network. The assembled genomes were analyzed with Pangolin software and assigned to the B.1 lineage, which is widely circulating in Europe.

Illness perceptions, depression and anxiety in informal carers of persons with depression: a cross-sectional survey.

PURPOSE: To examine the illness perceptions of informal carers of persons with depression, using the theoretical framework of Leventhal's Common-Sense Model (CSM) and to determine whether these illness perceptions are predictors of anxiety and depression, as measures of psychological well-being. METHODS: A cross-sectional survey was conducted with 94 Maltese individuals caring for a person with depression within a community setting. The informal carers completed the modified Illness Perception Questionnaire (IPQS-Relatives version) and the Hospital Anxiety and Depression Scale (HADS). Data were analysed using descriptive statistics, Spearman's rank order correlations and ANCOVA regression models, to identify predictors of anxiety and depression respectively in the informal carers. RESULTS: The informal carers perceived depression as a cyclical condition, having negative consequences on both the patient and on themselves. Participants perceived the causes of depression to be mainly psychosocial in nature and generally viewed the treatment as effective. Caring for a person with depression was perceived as having a considerable negative emotional impact on them. Years of caring was identified as a predictor of anxiety accounting for 20.4% of the variance, and timeline chronicity beliefs, consequences (relative) and illness coherence were identified as predictors of depression, accounting for 56.8% of the variance. CONCLUSION: Illness cognitions are significant predictors of depression, thereby suggesting that cognition-based interventions may be effective in targeting depression in these informal carers. Thus, health professionals should explore the carers' personal understanding of the disease, their timeline beliefs and the perceived consequences of providing care, as they relate to their psychological well-being.

Haploinsufficiency for the erythroid transcription factor KLF1 causes hereditary persistence of fetal hemoglobin.

Hereditary persistence of fetal hemoglobin (HPFH) is characterized by persistent high levels of fetal hemoglobin (HbF) in adults. Several contributory factors, both genetic and environmental, have been identified but others remain elusive. HPFH was found in 10 of 27 members from a Maltese family. We used a genome-wide SNP scan followed by linkage analysis to identify a candidate region on chromosome 19p13.12-13. Sequencing revealed a nonsense mutation in the KLF1 gene, p.K288X, which ablated the DNA-binding domain of this key erythroid transcriptional regulator. Only family members with HPFH were heterozygous carriers of this mutation. Expression profiling on primary erythroid progenitors showed that KLF1 target genes were downregulated in samples from individuals with HPFH. Functional assays suggested that, in addition to its established role in regulating adult globin expression, KLF1 is a key activator of the BCL11A gene, which encodes a suppressor of HbF expression. These observations provide a rationale for the effects of KLF1 haploinsufficiency on HbF levels.

Hb Valletta [beta87(F3)Thr-->Pro] and Hb Marseille/Long Island [beta2(NA2)His-->Pro; (-1)Met-(+1)Val-(+2)Pro-Leu], in a unique compound heterozygote with a normal hemoglobin phenotype.

This study refers to the quantitative hemoglobin (Hb) phenotype of a 19-year-old female with Hb Valletta [beta87(F3)Thr-->Pro] in association with Hb Marseille/Long Island [beta2(NA2)His-->Pro; (-1)Met-(+1)Val-(+2)Pro-Leu] and a normal Hb electrophoretogram. The data serve to alert investigators to the possibility that relatives with apparently normal Hb phenotypes may be transmitting mutant alleles and suggest methods for identification.

A review of cis-trans interplay between DNA sequences 5' to the (G)gamma- and beta-globin genes among Hb F-Malta-I heterozygotes/homozygotes and beta-thalassemia homozygotes/compound heterozygotes, and the effects of hydroxyurea on the Hb F/F-erythrocyte; the need for large multicenter trials.

The biosynthesis of Hb F in place of the deficient Hb A could be a suitable treatment for beta hemoglobinopathies. Among newborn Hb F-Malta-I heterozygotes, it could be shown that the XmnI sequence alone had little, if any effect on gamma-globin gene expression, but interplay with the (AT)(X)T(Y) sites in cis and in trans may occur. In contrast, while the XmnI sequence is clearly correlated with gamma-globin levels in anemic adult beta-thalassemia (thal) homozygotes, the effect on F-erythrocyte numbers and Hb F/F-erythrocyte appears independent of the (AT)(X)T(Y) sites. Even at levels of hydroxyurea (HU) as low as 1.65 mg/kg/day (vs. 10 mg/kg/day on the high dose regime) it can be shown that although even a small increase of Hb F could be obtained, the effect was rarely translated into an increase in circulating hemoglobin (Hb). In most cases, the elevated Hb F level was dependent on the XmnI sequence and was due to increased numbers of F-erythrocytes or Hb F/F-erythrocyte or both. It seems that the bone marrow of thalassemia homozygotes may be more sensitive to myelosuppression by HU possibly due to medullary inflammation. While the data are consistent with loop models of globin switching mechanisms, there is urgent need for large, hypothesis driven, multicenter trials of molecules that could maintain or re-induce high Hb F levels in beta-thal and subject to genetic and epigenetic constraints including inflammation.

Developmental effect of the XmnI site on Ggamma-globin gene expression among newborn Hb F-Malta-I [Ggamma117(G19)His-->Arg, CAT-->CGT] heterozygotes and adult beta+ -Thalassemia homozygotes.

Hb F-Malta-I [Ggamma117(19)His-->Arg, CAT-->CGT] is a stable and benign variant of Hb F found in 1.8% of Maltese newborn. We studied 120 Hb F-Malta-I heterozygotes and four Hb F-Malta-I homozygotes. The mean proportion of Ggamma-F-Malta-I in Hb F was 0.26 +/- 0.03 for the Hb F-Malta-I heterozygotes and 0.58 +/- 0.06 for the Hb F-Malta-I homozygotes. The Hb F-Malta-I allele was shown to occur on a background of the common Mediterranean haplotype Va [+ + - - - - - + + -]. Furthermore, the common Mediterranean haplotypes Va, IIIb [- + + + - + + + + -], I [+ + - - - - - + + +] and II [- + - + + - + + + +] accounted for most (66.2%) of the wild-type alleles among the tested Hb F-Malta-I heterozygotes. Different genotypes at the 5' epsilon HincII, Ggamma and Agamma HindIII, and 3'psibeta HincII sites (but not at the 5' Ggamma XmnI site) were found to be linked to significant variations in the proportion of Ggamma-F-Malta-I and Ggamma-globins in the Hb F of newborn Hb F-Malta-I heterozygotes. Moreover, the 5' Ggamma XmnI site was found to be associated with variations in Hb F and Ggamma-globin levels in a population of adult Maltese beta-thalassemia (thal) homozygotes. This implies that a determinant linked to the XmnI site which effects Ggamma-globin gene expression is active in anemic adults but not in normal infants.

Molecular genetics of tetrahydrobiopterin (BH4) deficiency in the Maltese population.

Deficient activity of the Dihydropteridine Reductase enzyme (DHPR; EC 1.5.1.34; OMIM 261630) is due to mutations in the Quinoid Dihydropteridine Reductase gene on 4p15.3 (QDPR; RefSeq NM_000320). It results in defective recycling of tetrahydrobiopterin (BH(4)) and homozygotes have a rare form of atypical Hyperphenylalaninaemia and Phenylketonuria (aPKU). The heterozygote frequency in the Maltese population is high at 3.3%. The more recently described and rarer type of BH(4) deficiency due to Sepiapterin Reductase enzyme deficiency (SR; EC 1.1.1.153; OMIM 182125), which presents as an atypical form of Dopa Responsive Dystonia (DRD) [L. Bonafe, B. Thony, J.M. Penzien, B. Czarnecki, N. Blau, Mutations in the sepiapterin reductase gene cause a novel tetrahydrobiopterin-dependent monoamine-neurotransmitter deficiency without hyperphenylalaninemia, Am. J. Hum. Genet. 69 (2001) 269-277; B.R.G. Neville, R. Parascandalo, S. Attard Montalto, R. Farrugia, A.E. Felice, A congenital dopa responsive motor disorder: a Maltese variant due to sepiapterin reductase deficiency, Brain 128 (Pt10) (2005) 2291-2296.] has also been identified at high frequency (4.6%) in this population. Two mutations, the c.68G>A in QDPR (p.G23D), and the new SPR, IVS2-2A>G mutation at the splice site consensus sequence in intron 2 of the Sepiapterin Reductase gene (SPR; RefSeq NM_003124) on 2p14-p12, were found to be the sole causative mutations in all the patients with DHPR deficiency and SR deficiency studied. All parents were heterozygotes for the corresponding mutation and showed no clinical symptoms. Three polymorphisms, c.96C>T (p.A32A), c. 345G>A (p.S115S) and c. 396G>A (p.L132L), have also been identified in the QDPR gene, defining four wild-type frameworks, useful in molecular epidemiology studies. The c. 68G>A mutation in QDPR was found only on framework I, suggesting a founder effect. In contrast no additional sequence diversity was found in the SPR gene whether in wild-type or mutant alleles which is also consistent with a founder effect.