Molecular Characterisation of α‐ and β‐Thalassaemia among Indigenous Senoi Orang Asli Communities in Peninsular Malaysia

Thalassaemia is a public health problem in Malaysia, with each ethnic group having their own common mutations. However, there is a lack on data on the prevalence and common mutations among the indigenous people. This cross‐sectional study was performed to determine the common mutations of α‐ and β‐thalassaemia among the subethnic groups of Senoi, the largest Orang Asli group in Peninsular Malaysia. Blood samples collected from six Senoi subethnic groups were analysed for full blood count and haemoglobin analysis (HbAn). Samples with abnormal findings were then screened for α‐ and β‐globin gene mutations. Out of the 752 samples collected, 255 showed abnormal HbAn results, and 122 cases showing abnormal red cell indices with normal HbAn findings were subjected to molecular screening. DNA analysis revealed a mixture of α‐ and β‐globin gene mutations with 25 concomitant cases. The types of gene abnormalities detected for α‐thalassaemia were termination codon (T>C) Hb CS (α^CSα), Cd59 (G>A) haemoglobin Adana (Hb Adana) (α^Cd59α), initiation codon (ATG>A‐G) (α^IniCdα), two‐gene deletion (–^SEA), and single‐gene 3.7‐kb deletion (‐α^3.7). For β‐thalassaemia, there were Cd26 (G>A) Hb E (β^E), Cd19 (A>G) Haemoglobin Malay (Hb Malay) (β^Cd19), and IVS 1–5 (G>C) (β^{IVS 1–5}).     

Hemizygous deletions on chromosome 1p21.3 involving the DPYD gene in individuals with autism spectrum disorder

We describe the identification and clinical presentation of four individuals from three unrelated families with hemizygous deletions involving the DPYD gene at chromosome 1p21.3. DPYD encodes dihydropyrimidine dehydrogenase, which is the initial and rate-limiting enzyme in the catabolism of pyrimidine bases. All four individuals described met diagnostic criteria for autism spectrum disorder with severe speech delay. Patient 1's deletion was originally reported in 2008, and more detailed clinical information is provided. Subsequently, this male individual was found to have a missense mutation in the X-linked PTCHD1 autism susceptibility gene, which may also contribute to the phenotype. Patients 2 and 3 are siblings with a novel deletion encompassing the DPYD gene. In their mother, the genomic region deleted from chromosome 1p21.3 was inserted into chromosome 10. A fourth proband had a novel 10-kb intragenic deletion of exon 6 of the DPYD gene detected on a higher resolution microarray. Our study suggests that hemizygous deletions involving the DPYD locus present with variable phenotypes which can include speech delay and autistic features, and may also be influenced by additional mutations in other genes, issues which need to be considered in genetic counseling.     

Comparative study of the metal accumulation in Hysterothalycium reliquens (nematode) and Paraphilometroides nemipteri (nematode) as compared with their doubly infected host,Nemipterus peronii (Notched threadfin bream)

In February 2013, forty-seven Notched threadfin bream, the Nemipterus peronii, were sampled from the eastern coastal waters of the South China Sea. The concentration of various elements, namely cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), strontium (Sr), manganese (Mn), selenium (Se), Lead (Pb), nickel (Ni), aluminum (Al), arsenic (As), iron (Fe), and Zinc (Zn) were analyzed in the liver, muscle, and kidney organs of the host, as well as in their parasites Hysterothalycium reliquens (nematode) and the Paraphilometroides nemipteri (nematode), using inductively coupled plasma mass spectrometry (ICP-MS). The former group of parasites showed highest accumulation capacity for Cr, Cu, Fe, Mn, Se, Ni, and Zn while the latter group had high accumulation potential of As, Hg, Cd, Al, Pb, and Sr. The divergence in heavy-metal accumulation profiles of both nematodes is linked with the specificity of microhabitats, cuticle morphology, and interspecific competition. The outcome of this study indicates that both parasite models can be used for biomonitoring of metal pollution in marine ecosystems.     

Dendritic fibromyxolipoma: A variant of spindle cell lipoma with extensive myxoid change,with cytogenetic evidence

Dendritic fibromyxolipoma (DFML), a rare, recently described distinct benign soft tissue tumor, has many clinicopathological features reminiscent of spindle cell lipoma and solitary fibrous tumor with myxoid change. It is distinguished histologically from both entities by the presence of spindle and stellate cells with dendritic cytoplasmic prolongations, prominent myxoid stroma with abundant keloidal collagen and occasional small plexiform vascular proliferation. We describe a case of histologically confirmed DFML of the left shoulder in a 67‐year‐old male, in which subsequent cytogenetic analysis revealed deletion involving 13q14.3 region in all the tumor cells, typically detected in spindle cell lipoma. In the presence of many clinicopathological similarities between DFML and spindle cell lipoma including chromosomal abnormalities, we postulate that DFML is merely a rare variant of spindle cell lipoma with extensive myxoid degeneration, and may not be considered as a separate entity. The possible differential diagnosis and their distinguishing features are briefly discussed.     

Emergence of novel coronavirus and progress toward treatment and vaccine

In late December 2019, a group of patients was observed with pneumonia‐like symptoms that were linked with a wet market in Wuhan, China. The patients were found to have a novel coronavirus genetically related to a bat coronavirus that was termed SARS‐CoV‐2. The virus gradually spread worldwide and was declared a pandemic by WHO. Scientists have started trials on potential preventive and treatment options. Currently, there is no specific approved treatment for SARS‐CoV‐2, and various clinical trials are underway to explore better treatments. Some previously approved antiviral and other drugs have shown some in vitro activity. Here we summarize the fight against this novel coronavirus with particular focus on the different treatment options and clinical trials exploring treatment as well as work done toward development of vaccines.     

Irinotecan-induced mucositis manifesting as diarrhoea corresponds with an amended intestinal flora and mucin profile

Chemotherapy-induced diarrhoea is a major oncological problem, caused by the cytotoxic effects of cancer chemotherapy. Irinotecan is linked with severe mucositis and diarrhoea, the mechanisms of which remain poorly understood. Bacterial β-glucuronidase is thought to be involved in the metabolism of irinotecan, implicating the intestinal flora. Intestinal mucins may also be implicated in the development of chemotherapy-induced diarrhoea. Rats were treated with 200 mg/kg of irinotecan and killed at 96, 120 and 144 h. The rats were monitored for diarrhoea. Pathology and immunohistochemical staining was performed. The samples were cultured and faecal DNA was analysed using real-time polymerase chain reaction. Severe diarrhoea was observed from 72 to 96 h. A decrease in body mass was also observed after treatment. Significant changes in goblet cell numbers (both complete and cavitated cells) were observed in the small and large intestines. Changes in MUC gene expression were observed in the small intestine only. Modifications were observed to the intestinal flora profile, especially Escherichia coli , and an increase in the expression of β-glucuronidase was detected. In conclusion, irinotecan-induced diarrhoea may be caused by an increase in some β-glucuronidase-producing bacteria, especially E. coli , exacerbating the toxicity of active metabolites. Accelerated mucous secretion and mucin release may also contribute to the delayed onset of diarrhoea.     

Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan

Rafiq MA, Ansar M, Marshall CR, Noor A, Shaheen N, Mowjoodi A, Khan MA, Ali G, Amin‐ud‐Din M, Feuk L, Vincent JB, Scherer SW. Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan. To date, of 13 loci with linkage to non‐syndromic autosomal recessive mental retardation (NS‐ARMR), only six genes have been established with associated mutations. Here we present our study on NS‐ARMR among the Pakistani population, where people are traditionally bound to marry within the family or the wider clan. In an exceptional, far‐reaching genetic survey we have collected more than 50 consanguineous families exhibiting clinical symptoms/phenotypes of NS‐ARMR. In the first step, nine families (MR2‐9 and MR11) with multiple affected individuals were selected for molecular genetic studies. Two families (MR3, MR4) showed linkage to already know NS‐ARMR loci. Fifteen affected and 10 unaffected individuals from six (MR2, MR6, MR7, MR8, MR9 and MR11) families were genotyped by using Affymetrix 5.0 or 6.0 single‐nucleotide polymorphism (SNP) microarrays. SNP microarray data was visually inspected by dChip and genome‐wide homozygosity analysis was performed by HomozygosityMapper. Additional mapping was performed (to exclude false‐positive regions of homozygosity called by HomozygosityMapper and dChip) on all available affected and unaffected members in seven NS‐ARMR families, using microsatellite markers. In this manner we were able to map three novel loci in seven different families originating from different areas of Pakistan. Two families (MR2, MR5) showed linkage on chromosome 2p25.3‐p25.2. Three families (MR7, MR8, and MR9) that have been collected from the same village and belong to the same clan were mapped on chromosome 9q34.3. MR11 maps to a locus on 9p23‐p13.3. Analysis of MR6 showed two positive loci, on chromosome 1q23.2‐q23.3 and 8q24.21‐q24.23. Genotyping in additional family members has so far narrowed, but not excluded the 1q locus. In summary, through this study we have identified three new loci for NS‐ARMR, namely MRT14, 15 and 16.