ABSTRACT
Purpose: Hereditary causes are an important etiological category of childhood blindness. This study reports the real?world experience of a developing ocular genetic service. Methods: The study was carried out from Jan 2020 to Dec 2021 jointly by the Pediatric Genetic Clinic and the Department of Ophthalmology of a tertiary care hospital in North?West India. Children presenting to the genetic clinic with congenital or late?onset ocular disorder(s) and any individual (irrespective of age) suffering from an ophthalmic disorder and referred by an ophthalmologist for genetic counseling for himself/herself and/or his/her family member(s) were included. Genetic testing (exome sequencing/panel?based sequencing/chromosomal microarray) was outsourced to third?party laboratories with the cost of the test being borne by the patient. Results: Exactly 8.6% of the registered patients in the genetic clinic had ocular disorders. Maximum number of patients belonged to the category of anterior segment dysgenesis, followed by microphthalmia anophthalmia coloboma spectrum, lens disorders, and inherited retinal disorders in decreasing numbers. The ratio of syndromic ocular to isolated ocular disorders seen was 1.8:1. Genetic testing was accepted by 55.5% of families. The genetic testing was clinically useful for ~35% of the tested cohort, with the opportunity for prenatal diagnosis being the most useful application of genetic testing. Conclusion: Syndromic ocular disorders are seen at a higher frequency compared to isolated ocular disorders in a genetic clinic. Opportunity for prenatal diagnosis is the most useful application of genetic testing in ocular disorders.
ABSTRACT
Abstract The mucopolysaccharidoses (MPS) are a relatively uncommon group of inherited metabolic disorders. MPSs should be suspected in a child with coarse facies, organomegaly, recurrent respiratory tract infections, developmental delay, and hernias. Early diagnosis and treatment can greatly improve the quality of life in these children. In this study we studied 46 MPS patients diagnosed on enzyme and/or DNA testing and we found that the MPS II was the most common type followed by MPS I and MPS IVA. While the mean age of onset of symptoms was 12 months, the mean age at diagnosis was 4.5 years, a significant delay. One of major presenting features was recurrent respiratory problems, more prevalent in MPS II cases. Many patients also had short stature and contractures. Increasing awareness among physicians is of paramount importance for the early diagnosis and optimal treatment and prevention by prenatal testing and counselling.
ABSTRACT
Background & objectives: Studies have demonstrated the effect of CYP2C9 (cytochrome P450) and VKORC1 (vitamin K epoxide reductase complex) gene polymorphisms on the dose of acenocoumarol. The data from India about these gene polymorphisms and their effects on acenocoumarol dose are scarce. The aim of this study was to determine the occurrence of CYP2C9*2,*3 and VKORC 1 -1639G>A gene polymorphisms and to study their effects on the dose of acenocoumarol required to maintain a target International Normalized Ratio (INR) in patients with mechanical heart valve replacement. Methods: Patients from the anticoagulation clinic of a tertiary care hospital in north India were studied. The anticoagulation profile, INR (International Normalized Ratio) values and administered acenocoumarol dose were obtained from the clinical records of patients. Determination of the CYP2C9*2,*3 and VKORC1 -1639G>A genotypes was done by PCR-RFLP (restriction fragment length polymorphism). Results: A total of 111 patients were studied. The genotype frequencies of CYP2C9 *1/*1,*1/*2,*1/*3 were as 0.883, 0.072, 0.036 and that of VKORC1 -1639G>A for GG, AG, and AA genotypes were 0.883, 0.090, and 0.027, respectively. The percentage of patients carrying any of the variant alleles of CYP2C9 and VKORC1 in heterozygous or homozygous form was 34% among those receiving a low dose of ≤20 mg/wk while it was 13.8 per cent in those receiving >20 mg/wk (P=0.014). A tendency of lower dose requirements was seen among carriers of the studied polymorphisms. There was considerable variability in the dose requirements of patients with and without variant alleles. Interpretation & conclusions: The study findings point towards the role of CYP2C9 and VKORC1 gene polymorphisms in determining the inter-individual dose variability of acenocoumarol in the Indian patients with mechanical heart valve replacement.