Since the early 1950’s, Singapore is internationally known as the guppy-breeding centre. At least 40 different colour varieties of guppies are cultured in Singapore, with each farm specialising in 10 to 15 varieties. These fancy varieties have been developed by skilful farmers through intensive and continual selective breeding. Genes controlling background body pigmentation such as albino (a), blond (b), gold (g) and blue (r) are autosomally inherited and recessive to their wild-type alleles which produce drab olive-brown background coloration. Colour patterns which are superimposed onto wild-type background coloration are due to genes located on the sex chromosomes. These
sex-linked colour genes are dominant and sex-limited to males as their expression requires male hormones. Y-linked colour pattern genes carried by males are inherited only along the paternal line while X-linked genes are present in both sexes. Among the guppy varieties produced locally, only two Y-linked genes, Ssb and Sst, that control snakeskin tail and body patterns, respectively, have been found in varieties with snakeskin-like reticulations. Single colour genes that are both X- and Y-linked produce red (Rdt), blue (Blt), green (Grt), black (Bt) and variegated (Var) patterns
on the caudal fin. The black caudal-peduncle of the Tuxedo variety is the result of Bcp, a gene that is both X- and Ylinked. Different combinations of colour pattern genes and background pigmentation genes as well as interactions among them give rise to various colour phenotypes. For
instance, the inclusion of Bcp in Snakeskin varieties causes black reticulations on the tail fin to be replaced by large, coarse black spots. Neon coloration is produced by interactions between the Ln (light turquoise) gene with Blt, Rdt and Bcp.
Geographically isolated populations of endemic orchids have evolved and adapted to an existence within specifi c ecological niches. These populations are highly susceptible to anthropogenic
infl uences on their microhabitats. The primary objective of conservation programs is the restoration of endangered populations to their ecologically sustainable levels, and the fi rst stage in the process of conservation involves estimation of molecular diversity at the level of the population. The approach described in this article involves the application of RAPD, Microsatellites and Chloroplast DNA markers for the characterization of the genetic structure of Paphiopedilum rothschildianum and Phalaenopsis gigantea, two endangered and endemic orchids of Sabah. This study has isolated a total of 96 microsatellite loci in P. rothschildianum and P. gigantea, 42 specifi c primer pairs have been designed for amplifi cation of microsatellite loci and are currently being applied to screen the breeding pools. The Chloroplast DNA regions amplifi ed by the primer pairs trnH-psbA and trnL-trnF exhibit distinct polymorphisms and can be used to establish phylogenetic
relationships. The ability of microsatellite loci to cross-amplify selected varieties of orchids has been determined. The molecular markers developed will be applied to estimate population diversity
levels and to formulate long-term management strategies for the conservation of endangered species of orchids of Sabah.
Smaller family size and advancing parental age have increased the demand for prenatal diagnosis.
Prenatal cytogenetic diagnoses currently used, such as amniocentesis and chorionic villus
sampling, are usually not preferred by the expectant couples due to the risk imposed on the mother and child. High false positive rates (5%) of current non-invasive screening methods, such as serum analysts or ultrasound, cause a large number of unnecessary invasive practices to be performed, which apart from the associated risk, place considerable psychological distress on the couples
involved (Wald et al., 1999). (Copied from article).
DNA microarray technology has permitted large scale parallel analysis of gene expression of several diseases, including cancers. Real-time PCR has become a well-established procedure for
quantifying levels of gene expression. We evaluated Real-Time PCR to validate differentially expressed genes identified by DNA arrays. Gene expression of three different grade of transitional cell carcinoma (TCC) of human bladder cancer was determined using microarray slide containing cancer-related genes. Data obtained were sorted according based on the ratios between Cy3 and Cy5 dyes used and revealed 119, 235 and 183 differentially expressed genes in TCC WHO Grades I, II and III, respectively. Real-time PCR used SYBR Green-1 dye detection to validate relative change in gene expression. Real- Time PCR confirmed the change in gene expression of 17 of 28 (75%) genes identified by microarray. Real-Time PCR also suggest that genes identified by microarray with two or higher fold change cannot be eliminated as false nor be accepted as true without validation. Real-Time PCR based on SYBR Green- 1 is well-suited to validate DNA array results because it is quantitative, rapid and requires less RNA compared to the conventional assays.
Molecular techniques involving the application of DNA based molecular markers for the conservation and management of endemic and endangered species have assumed significance as
genome sequencing projects have generated an extensive database which can be mined for informative genomic regions. Scientific approaches towards conservation involve several stages, which encompass determination of appropriate genomic regions for characterization, design and testing of specific molecular markers, screening of multiple populations and statistical treatment and
interpretation of data. Population data can be utilized to develop controlled breeding and relocation programs aimed at ensuring that genetic diversity within populations of endangered species is
sustained within the context of an overall conservation program. The information derived as a result of this approach can be applied to establish a scientific and legal framework for the conservation of endemic species. Species specific genomic markers can be applied to enforce the implementation of CITES within the guidelines of a national biodiversity conservation policy.
Chronic Myeloid Leukemia (CML) is a clonal disorder thought to originate in a single abnormal haematopoietic stem cell. This myeloproliferative fatal stem cell disorder comprises
approximately 14% of all leukemias. In most cases, CML runs a triphasic course, which includes an initial chronic phase that transforms eventually into a blastic phase resembling acute leukemia. In 60%- 80% of patients, an intermediate or accelerated phase precedes the terminal blastic phase. Accelerated phase and blastic phase sometimes are lumped together and considered to be
advanced phase CML. The entire continuum from chronic phase to blastic phase lasts a median of 3 to 5 years . This time period can be broken down in to the chronic phase which if untreated,
lasts for 2 to 5 years and finally the fatal blastic phase, which lasts from 3 to 6 months. A patient can present in any of these 3 stages.
This paper reports on a preliminary genetic investigation of two commercially cultured oyster species, white and black scar oysters, Crassostrea belcheri and C. iredalei, respectively. A total
of 68 individuals from three different areas in Malaysia namely a C. belcheri sample from Semporna (Sabah) and two populations of C. iredalei from Trai (Sabah) and Setiu (Terengganu) were
collected and analysed based on sequence analysis of cytochrome oxidase subunit I (COI). Alignment of COI gene was done using Alignment Explorer/CLUSTAL in Mega4.1. Genetic distances
within and between populations were calculated using Kimura 2-parameter. Phylogenetic dendograms were generated by Neighbour-Joining (NJ) and Maximum Parsimony (MP) methods.
The ingroup taxa were divided into two main clusters separating C. iredalei and C. belcheri with 99% bootstrap value. The two C. iredalei populations were homogeneous suggesting high
connectivity in the South China Sea for this species. The common central haplotype in the minimum spanning networks programme is believed to be the ancestral variant for the two species. The
findings from this study provides important baseline data for the aquaculture, management and monitoring of cultured populations of the oyster species.
Termitomyces are delicious edible mushrooms found in Africa and South-East Asia including Malaysia. These mushrooms were found to grow symbiotically with termites around termite nests. Numerous efforts have been made worldwide to develop a cultivation method for these mushrooms. Unfortunately, none of those attempts were successful. The main obstacles encountered were the difficulty to identify and isolate pure termitomyces culture. The problem became prevalent as the culture gets contaminated by other fungi. Termitomyces can easily be identified by its mushroom fruiting body eventually but certainly not at the mycelium and hyphea stages. In this study a simple PCR-based genetic marker detection method for confirmation of termitomyces at any culture stage was developed. Using this method, four distinctive PCR assays
were developed using specific PCR primers designed based on the DNA sequence of the termitomyces mushroom. The PCR results showed that the PCR assays using intact termitomyces
DNA as template was not suitable for this purpose. However, PCR using BamHI and EcoRI predigested termitomyces DNA as template showed identical polymorphism pattern for both
termitomyces mushroom DNA and termitomyces culture DNA. Thus, the method reported here can be used for the identific.
Microsatellites or simple sequence repeats (SSRs) are tandem repeats of DNA of 1-6 bp long. They ubiquitously occur in both eukaryotic and prokaryotic genomes. Because of their abundance,
they have widespread applications in both animal and plant sciences; such as varietal identification, genetic mapping, QTL mapping, phylogenetic and diversity studies. Thus, SSRs have become valuable DNA markers for molecular biologists and geneticists. Microsatellites are markers
of choice for many molecular geneticists because of their hypervariability, codominant
inheritance, multi-allelism and PCR-based assaying of variations that are amenable to automation and high throughput assay. However, the utilization of microsatellite markers in the past was
hampered by its laborious de novo isolations and species-specific nature.
Down Syndrome (DS), is a complex genetic disease resulting from the presence of 3 copies of chromosome 21. It is the most common autosomal abnormality among live births and the most commonly recognized genetic cause of mental retardation. The only well established risk factor for DS is advanced maternal age. The Human Genome Center , University Sains Malaysia, Kelantan has been carrying out cytogenetic studies in DS patients. Here we, report the karyotype pattern of Down Syndrome patients in correlation with maternal age, among referral cases to our Center.
This study was part of the larger studies to isolate and characterize gene related to flowering in teak. This study isolated differentially expressed genes of teak flowering tissues. One of the genes encodes plant protein kinases highly homologous to the AtSK-II of Arabidopsis GSK3/SHAGGY subfamily. The gene was named as Tectona grandis SHAGGY kinase (Tg-SK). The protein sequence of this gene contained the characteristic catalytic domain of GSK-3/SHAGGY protein kinase. The gene also shows the same genomic organization of 11 introns and 12 exons. Although the size of the introns varies, the positions of exon/intron boundaries are very similar to AtSK-II. The discovery of this gene in teak, which is a forest tree species, supports the hypothesis, which suggested the gene is found in all eukaryotes.
Cystic Fibrosis (CF) is a life-threatening inherited disease that particularly affects the airways and digestive systems, which is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. CF is considered as the most common autosomal recessive disorder in the Caucasian population. However, the prevalence of this disease amongst Asians is considered to be low, hence the lack of awareness of this disease amongst geneticists and physicians in Malaysia. This review will describe the features of CF, its molecular genetics, the current classification of CFTR mutation classes, the genotype-phenotype correlations, the effects of modifier genes, and the discourse of the disease pathogenesis, in the hope of raising public awareness of the condition and ultimately to improve the clinical and social care of those affected by CF in Malaysia.
In various biological studies, for example those in population genetics, conservation biology, forensic science, gene mapping, breed, strain and population characterization and identification, marker assisted selection and the identification of cryptic species complexes, codominant genetic markers play important roles. The information that can be gained from them are far superior than those from dominant markers like random amplified polymorphic DNA (RAPD), amplified fragment length polymorphisms (AFLP), direct amplification of length polymorphisms (DALP) and randomly amplified microsatellites (RAM) or inter simple sequence repeats (ISSR).
Roselle (Hibiscus sabdariffa L.) from Malvaceae family is an annual crop with potential for use by many industries including food, animal feed, neutraceutical, cosmeticeutical and pharmaceutical industries. Its origin is not fully known but it is believed to be from West Africa, although the plant is found native from India to Southeast Asia. The calyxes, stems and leaves are acid in flavour. The juice is produced from the calyces, and it is claimed to be a prohealth drink due to its high contents of ascorbic acid, anthocyanins and other antioxidants.
The blood of the Painted Storks (Mycteria leucocephala) and the Milky Storks (M. cinerea) from Malaysia were collected
invasively from the breeding site. The blood was dropped on to FTA® cards and stored at room temperature. DNA was isolated from
the FTA® cards through a modification of the Wizard DNA Purification kit (Promega) procedure and PCR was performed with 11 pairs
of microsatellite primers of the American Wood Stork (M. americana). The collection of a drop of blood onto the card is superior to the
usual practice of collecting about five ml of blood into a vacuum tube as it causes fewer traumas to these sensitive birds. Moreover, this
collection procedure can be adopted for use in various wild animal species which are usually found in the remote areas of Malaysia as
the sample collection cards can be transported back to the laboratory at room temperature. Our procedure allows the typing of several
molecular genetic markers from just a drop of blood collected in the field and stored at room temperature alleviating the need for storage
in expensive deep freezers or liquid nitrogen tanks.
Basal stem rot disease caused by the basidiomycete fungus, Ganoderma boninense is the most serious disease of oil palm in Malaysia. The disease can be identified by dry rotting of internal parts of the stem with fruiting bodies or basidiomata of the fungus occurring at the oil palm stem base. The stem lesion allows the basal stem rot disease to be distinguished from the other root diseases
(Turner, 1981).
Malaysia, experienced two epidemic waves of HPAI; its fi rst outbreak of HP H5N1 in August 2004 that occurred in the state of Kelantan and the second and subsequent outbreaks in February–March 2006 in three states on the west coast of Malaysia namely Wilayah Persekutuan
Kuala Lumpur, Perak and Penang. Five outbreaks occurred in village chickens and one in a multi-species enclosure of birds in a bird park resort facility. Molecular epidemiological studies by genomic sequencing and phylogenetic analyses of the viruses isolated showed that the
virus isolated from WP Kuala Lumpur is of the V-genotype and it originated from Hunan China, two viruses were found to be similar to the Fujian/Hunan strains and other viruses were similar to the Vietnam/ Thailand strains.
The genetic relationship between any two populations is a function of the differences between them in allele frequencies, with this relationship commonly expressed in terms of a genetic distance. For example if the two populations are homozygous for different alleles at a particular locus, the distance is the maximum possible whereas if the allele frequencies in the two populations are identical, the distance is zero. The estimated genetic distances may vary among loci. Thus, the most accurate measures of relationships will be obtained by averaging many loci (Nei, 1978). In plant and animal breeding, it is expected that a cross between two individuals originating from two populations with a large genetic distance between them will result in maximum heterosis or hybrid vigour. Many estimates of genetic distances are available in the literature but Nei’s standard genetic distance, D, (Nei, 1972, 1978) had been extensively used in studies of human, animal and plant varieties, races, breeds, strains, populations, species and genera.
Quality of planting materials determines future successes of plantations and subsequent endeavours in the life cycle. Oil palm (Elaeis guineensis) breeding triggered an industry in Malaysia through “Plant Introduction” with the establishment of the first oil palm plantation. At the wake of the oil palm industry, plantations utilised the dura planting material. The hallmark discovery of the single gene inheritance for shell thickness led to the prolific dura x pisifera (DxP) derived tenera planting material. Subsequent parental inbred lines developed in recurrent selections, crossed and progeny tested exploiting heterosis had boosted yields. Further improvements were foresighted and executed in the widening of the genetic pool and collections of germplasm in centres of origin/diversity in Africa and Latin America. Field Genebank of the Malaysian Palm Oil Board (MPOB) forms the world’s largest ex situ oil palm conservation programme. This programme enabled the developments of elite breeding populations harbouring specialty oils and products. Meanwhile, opening of large oil palm areas by the Federal Land Development Authority (Felda) set the momentum in rapid expansion of the industry. Felda is an exemplary in wealth creation and quality of life (QOL). Resettlements of landless farmers into Felda schemes, employing modern farming, mainly in oil palm has helped eradicate poverty and uplifting QOL among settlers, employees and their families. Impacts of the success in wealth creation and its distribution leading to better QOL, rooted from breeding through the supply of quality planting materials. Phenotypic expressions of the planting materials were realised through genotypic and environment interactions; the former through breeding, the latter through agronomic practices. Efforts in oil palm breeding helped paved the way to a mammoth industry, contributing to the nation economic growths, impacting livelihood of the people. Further progress in yield is expected from clones, where breeding has a role in the supply of quality ortets. Genetic potential of planting materials can be further exploited through interdisciplinary approach in breeding, biotechnology and genomics. With continuing wealth creation, the oil palm saga continues. Once wealth is created, QOL will follow.
Population growth and rise in per capital income have influenced the demand for convenience foods and a meat protein-rich diet. The per capital consumption of beef which had increased from 3.89 kg in 1980 to 5.49 kg in 2006 (DVS, 2006/2007) had resulted in an increased in demand for beef at the rate of 6.2% annually. The local beef production although recorded a 2.5% increased over the last 10 years, is still unable to meat the increasing national demand for beef. In 2008, local production of beef is about 38,250 mt. could only meet about 26.7% of the national demand (DVS, 2008). The gap between supply and demand for beef is expected to widen in the next decades unless efforts is been made to accelerate local production. The lack of number of quality breeding stocks and unorganized breeding system had been the major factors that contribute to the slow growth of the local beef industry.