A cytogenetic survey 01 124 children in lour special schools for the mentally handicapped was carried out to determine the contribution of chromosomal abnormalities to the aetiology of mental retardation in these children. All the children were karyotyped employing the G·banding technique 01 43 (34.7%) with an abnormal chromosome complement, 40 had Down's Syndrome, and 3 had other chromosomal abnormalities, namely a translocation 1;17, a mosaic male/trisomy 18 and a Klinefelter's syndrome. Polymorphic variants involving chromosomes 1, 9, and 14 were also observed. Two other children showed variants of the Y chromosome (one a small Y and the other a metacentric Y). The possible contribution by these abnormal variants to mental retardation is discussed. Details of the abnormal cytogenetic findings are reported.
Over an 18 month period, 34,522 livebirths were delivered in the Maternity Hospital, Kuala Lumpur. 36 of them had Down's Syndrome. Based on our findings, the incidence of Down's syndrome among the Malaysian babies born in this hospital was 1:959 livebirths. According to racial distributions, the incidence among Malay was 1:981 livebirths, Chinese 1:940 livebirths, and Indian 1:860 livebirths. Our incidence was lower than those from the Western populations. Unlike others' studies, there was also a female preponderance of Down's syndrome among the Malaysian babies.
Over an 18 month period, 34,495 livebirths were delivered in the Kuala Lumpur Maternity Hospital. 36 neonates (1.044 per 1000 livebirths) had Down's syndrome. The observed rates of Down's syndrome per 1000 livebirths by single year intervals of maternal age were calculated. By using the discontinuous slope model, our study showed that the incidence of Down's syndrome among the Malaysian liveborns increased markedly when the maternal age exceeded 35 years. This study also suggested that the Malay mothers had increased risk of producing babies with Down's syndrome at a later age than the Chinese and the Indians. However, a larger number of babies in each racial group needs to be studied to confirm this.
A prospective study was done to determine the incidence of cardiovascular malformations in neonates with Down's syndrome. 17/34 (50%) of the babies with Down's syndrome born at the Maternity Hospital, Kuala Lumpur, Malaysia had congenital heart defects. These included 7 cases of ventricular septal defect (VSD), 3 cases of patent ductus arteriosus (PDA), 2 cases of atrio-ventricular canal defect, 2 cases of ventricular septal defect with patent ductus arteriosus, 1 case of hypertrophic cardiomyopathy, 1 case of hypertrophic obstructive cardiomyopathy and 1 case of complex cyanotic heart. Only 8/17 (47%) of these babies had any clinical signs suggesting underlying cardiac defects. In view of the common occurrence of cardiac anomalies, it is recommended that echocardiographic screening should be carried out on all neonates with Down's syndrome.
The use of maternal age alone to identify pregnant mothers at risk of a fetus with Down's syndrome has recently been supplemented by maternal serum screening using biochemical markers such as alpha-protein, human chorionic gonadotrophin and oestriol. These tests have been reported to increase the sensitivity of antenatal detection of such fetuses from 35% to 67% with a false positive rate of 5%. However, these maternal serum markers may be affected by maternal weight, the smoking history of mothers and diabetes mellitus. Furthermore, such sensitivities are achieved only when gestational age is assessed accurately by ultrasound. Many further studies need to be carried out before the introduction of maternal serum screening into routine obstetric practice in Singapore. These include studies on the incidence of Down's syndrome in the local population, studies on the distribution of these serum markers in the second trimester of pregnancy, sensitivities and positive predictive values of such a test in the local population as well as the socio-economic implications of implementing such a screening test in the local obstetric population.
The chromosome in situ suppression hybridization or chromosome painting technic was applied to confirm and eliminate the markers involving chromosome 21 segments using a chromosome 21 DNA library. The library ATCCLL21SNO2 was amplified, directly biotinylated using the polymerase chain reaction. The results demonstrated a translocation of chromosome 21 material on chromosome 2 and X and eliminate the origin of the marker. Thus, the technique provides an important tool to complement the conventional G-banding technic.
Matched MeSH terms: Down Syndrome/diagnosis; Down Syndrome/genetics*
Down syndrome may be associated with many complications. Among the malignancies associated with Down syndrome, leukaemia is the most common. This is a case report of a patient with Down syndrome associated with both a retroperitoneal teratoma and a Morgagni hernia.
A sample of 204 handicapped children below 12 years of age consisting of 121(59.3%) males and 83 (40.7%) females who were classified into various types of mental and physical handicaps, were surveyed in April and May 1996. The majority of those with mental handicaps were Down Syndrome while those with cerebral palsy were the mostfrequent cause of physical handicaps. A structured questionnaire was used for interviewing the children parents to evaluate their attitude towards their handicapped children. The majority of the parents expressed their opinions that having handicapped children was not a burden to them although these children had to be given more attention. However, a significant minority felt that the child would be afinancial burden to the family and that he/she would restrict the social life of the family. The majority of the children were sent to school, as parents felt it was their duty to do so. For those children not attending school, the majority of parents felt that the children would not benefit by going. The others could not do so because offinancial constraints or because of the distance between home and school. For these children, provid-ing hostel facilities in a boarding school could be the answer. This study shows that parental love and support plays a major role in ensuring optimal growth and development of a handicapped child
There has been no recent report on the dermatoglyphics of the Malays (normal population as well as patients with Down's syndrome). A study on the frequencies of the dermal patterns (dermatoglyphics) of the digits, palms and hallucal areas was done therefore in 40 Malay patients with Down's syndrome and 200 unrelated normal controls. Only the patients with the standard 21 trisomy karyotype were included in the study. Comparison was made with the published data on studies done in various racial groups. Significant differences of the dermal patterns were found not only between the controls but also among patients of different races.
Matched MeSH terms: Down Syndrome/ethnology; Down Syndrome/genetics*
Objective: To assess if children with Down's Syndrome have a higher prevalence of otological abnormality compared to their normal counterparts in Malaysia.
Methodology: Thirty children with Down’s Syndrome and normal children underwent otoscope ear examination and impedance test in the ENT outpatients clinic in University Hospital Kuala Lumpur, Malaysia.
Results: The study showed that children with Down’s Syndrome had higher ontological disorders. Forty four percent had impacted wax compared to 14.4% in normal children. Twenty one percent of ears in the study group had refracted drums compared to 6.6% of control. Fifteen percent of ears in the study group had middle ear effusion compared to 3.4% in controls, 55% had a type B tympanogram compared to 8.3% in controls and 73.4% had auditory canal stenosis compared to 14.4% in controls.
Conclusion: Children with Down’s Syndrome thus have a higher incidence of ontological disorders.
Study site: ENT outpatient clincs, University Malaya Medical Centre (UMMC)
Matched MeSH terms: Down Syndrome/complications*; Down Syndrome/epidemiology*
We report a case of upper cervical instability associated with Down syndrome to highlight its potential progression to inflict cord compression and the rationale for surgical decompression and extended short segment occipito-axial fusion.
The objective of the study is to determine the proportion and different types of birth defects among the children born in Hospital Kuala Lumpur. A cross-sectional study was conducted for a period of 18 months where all consecutively born infants, dead or alive were included. There were total of 34,109 births recorded during this period. The proportion of birth defects in Hospital Kuala Lumpur was 3.1% (n = 1056). The commonest involved were the hematology system, (157.7 per 10,000 births), the central nervous system, genitourinary system and chromosomal anomalies. The proportion was significantly higher in males and in the Chinese (p < 0.001). The commonest abnormalities are Glucose 6 Phosphate Deficiency (157.7/10000), Down's syndrome (12.6/10000), thalassaemia (8.8/10000), cleft lip and/or palate (7.6/10000) and anencephaly (7.3/10000). Neural tube defect is common and ranked second after G6PD deficiency. There is a need for a birth defect registry to assess the extent of the problem in Malaysia.
Down syndrome was first described as Mongoloid children with European parentage. Although their facial features resemble Orientals or Asians, ocular findings have not been well-documented in Asians, especially Malaysians. Our aim was to identify the ocular findings of Malaysian children with Down syndrome.
We studied 253 women with a pregnancy complicated by a birth defect and 506 controls to determine the frequency and type of prenatal tests and the types of defects detected antenatally. Most women had at least one ultrasound examination, but the frequency of other screening tests was low. Only 38 (15%) of defects were detected antenatally (37 by ultrasound). Birth prevalence is unlikely to be affected by pregnancy termination.
Matched MeSH terms: Down Syndrome/diagnosis; Down Syndrome/epidemiology
Down syndrome is a common chromosomal anomaly. Few reported studies make reference to the ocular status in Asian children with Down syndrome. The purpose of this study was to determine the visual and binocular status of a sample of Down syndrome children in Malaysia.
Matched MeSH terms: Down Syndrome/complications; Down Syndrome/physiopathology*
Transient abnormal myelopoiesis (TAM) occurs in approximately 10% of neonates with Down syndrome. In most cases it resolves spontaneously. Life threatening complications such as cardiopulmonary and liver diseases have been described. We present here two cases which suggest that management of TAM in selected cases will have to be more aggressive.
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.