Meenal Agarwal

GALNS Mutations in Indian Patients With Mucopolysaccharidosis IVA

Mucopolysaccharidosis IV A (Morquio syndrome A, MPS IVA) is a lysosomal storage disease caused by the deficiency of N‐acetylgalactosamine‐6‐sulfatase (GALNS). The mutation spectrum in this condition is yet to be determined in Indians. We aimed to analyze the mutations in the GALNS gene in Asian Indians with MPS IVA. All the exons and the adjacent intronic regions of the gene were amplified and sequenced in sixty‐eight unrelated Indian families. We identified 136 mutant alleles comprising of 40 different mutations. We report twenty‐two novel mutations that comprise of seventeen missense (p.Asn32Thr, p.Leu36Arg, p.Pro52Leu, p.Pro77Ser, p.Cys79Arg, p.His142Pro, p.Tyr191Asp, p.Asn204Thr, p.Gly188Ser, p.Phe216Ser, p.Trp230Cys, p.Ala291Ser, p.Gly317Arg, p.His329Pro, p.Arg386Ser, p.Glu450Gly, p.Cys501Ser), three splice‐site variants (c.120 + 1G > C, c.1003‐3C > G, c.1139 + 1G > A), one nonsense mutation (p.Gln414*) and one frameshift mutation (p.Pro420Leufs*440). Eighteen mutations have been reported earlier. Among these p.Ser287Leu (8.82%), p.Phe216Ser (7.35%), p.Asn32Thr (6.61%) and p.Ala291Ser (5.88%) were the most frequent mutations in Indian patients but were rare in the mutational profiles reported in other populations. These results indicate that the Indian patients may have a distinct mutation spectrum compared to those of other populations. Mutant alleles in exon 1, 7 and 8 accounted for 44.8% of the mutations, and sequencing of these exons initially may be a cost‐effective approach in Asian Indian patients. This is the largest study on molecular analysis of patients with MPS IVA reported in the literature, and the first report from India.

Hemiconvulsion–hemiplegia–epilepsy syndrome with 1q44 microdeletion: Causal or chance association

Hemiconvulsion–hemiplegia–epilepsy (HHE) syndrome is a rare syndrome characterized by childhood onset partial motor convulsions, hemiplegia, and epilepsy in sequence. Exact pathogenesis is not clear. Here we are describing a 3‐year‐old girl with HHE syndrome with cytogenetic microarray (CMA) showing deletion of 1.8 Mb in 1q44 region. Along with HHE syndrome, the patient also had global developmental delay, subtle facial dysmorphism, and preaxial polydactyly. Clinical phenotype of 1q44 microdeletion syndrome is quite variable. Main clinical features are microcephaly, seizures, and abnormality of corpus callosum. We compared the patients phenotype with other patients in 10 previously published papers of 1q44 microdeletion syndrome. HNRNPU and FAM36A are two important genes in the deleted region. HNRNPU gene mediate long range control of SHH gene which is likely explanation of preaxial polydactyly in the present patient. HHE may be a chance co‐occurrence.

Recurrent pregnancy loss and apolipoprotein E gene polymorphisms: a case–control study from north India.

Citation Agarwal M, Parveen F, Faridi RM, Phadke SR, Das V, Agrawal S. Recurrent pregnancy loss and apolipoprotein E gene polymorphisms: a case–control study from North India. Am J Reprod Immunol 2010; 64: 172–178

Late termination of pregnancy for fetal abnormalities: The perspective of Indian lay persons and medical practitioners

The objective of this article was to ascertain the opinion of lay persons and medical practitioners in India regarding late termination of pregnancies (LTOP) for fetal abnormalities.

Newborn screening for congenital hypothyroidism, galactosemia and biotinidase deficiency in Uttar Pradesh, India

ObjectiveTo assess feasibility and recall rates for newborn screening for congenital hypothyroidism, galactosemia and biotinidase deficiency in a predominantly rural and inner city population in and around the City of Lucknow in Uttar Pradesh, India.DesignProspective observational study.SettingTwo tertiary-care and 5 district hospitals in and around Lucknow.ParticipantsAll babies born in above hospitals during the study period.MethodsHeel prick samples were collected after 24 hours of life. Dried blood spot TSH, total galactose and biotinidase were assayed by immunofluorometry. Age related cut-offs were applied for recall for TSH. For galactosemia and biotinidase deficiency, manufacturer-suggested recall cut-offs used initially were modified after analysis of initial data.Main outcome measureRecall rate for hypothyroidism, galactosemia and biotinidase deficiency.ResultsScreening was carried out for 13426 newborns, 73% of all deliveries. Eighty-five percent of those recalled for confirmatory sampling responded. Using fixed TSH cut off of 20 mIU/L yielded high recall rate of 1.39%, which decreased to 0.84% with use of age-related cut-offs. Mean TSH was higher in males, and in low birth weight and vaginally delivered babies. Eleven babies had congenital hypothyroidism. Recall rates with modified cut-offs for galactosemia and biotinidase deficiency were 0.32% and 0.16%, respectively.ConclusionAn outreach program for newborn screening can be successfully carried out in similar socio-cultural settings in India. For hypothyroidism, the high recall rate due to early discharge was addressed by age-related cut-offs.

Angelman syndrome and prenatally diagnosed Prader–Willi syndrome in first cousins†

Prader–Willi syndrome (PWS) and Angelman syndrome (AS) are caused by loss of function of imprinted genes in the 15q11–13 critical region. Reports of PWS and AS in close relatives within the same family are rare. We report on the diagnosis of a familial unbalanced 10;15 translocation causing AS in a child that led to the prenatal diagnosis of an unbalanced 10;15 translocation with resultant deletion of the Prader–Willi critical region in her maternal uncles offspring.

Clinical and mutation profile of multicentric osteolysis nodulosis and arthropathy.

Multicentric osteolysis nodulosis and arthropathy (MONA) is an infrequently described autosomal recessive skeletal dysplasia characterized by progressive osteolysis and arthropathy. Inactivating mutations in MMP2, encoding matrix metalloproteinase‐2, are known to cause this disorder. Fifteen families with mutations in MMP2 have been reported in literature. In this study we screened thirteen individuals from eleven families for MMP2 mutations and identified eight mutations (five novel and three known variants). We characterize the clinical, radiographic and molecular findings in all individuals with molecularly proven MONA from the present cohort and previous reports, and provide a comprehensive review of the MMP2 related disorders.

Neural tube defects: A need for population-based prevention program

through spinal defect and histopathological fi ndings.[2] Majority of NTDs are isolated/non-syndromic and are not associated with other congenital malformations. However in about 10% of the cases, NTD can be a part of genetic syndrome hence may follow Mendelian inheritance. The syndromes associated with neural tube defects include Walker-Warburg syndrome, Jarcho-Levin syndrome, Robert syndrome and Meckel-Gruber syndrome. Rarely, NTD can be associated with chromosomal abnormalities including trisomy 13 and 18, triploidy and other chromosomal rearrangement.[2] Association of these genetic syndromes are important to assess as fi nal outcome and risk of recurrence in these families depends upon the individual syndrome. In syndromes with autosomal recessive inheritance, risk of recurrence in the siblings of affected individual is 25% while isolated NTD follow multifactorial inheritance pattern. Risk of recurrence in the siblings of isolated cases of NTD is 2%-5% after one affected child and 10% after the birth of two affected children.

Prenatal diagnosis in India is not limited to sex selection

To the Editor: We read “Impact of Prenatal Technologies on the Sex Ratio in India: An Overview,” by Madan and Breuning,1 and, as a group of medical geneticists from India, we wish to express our concern regarding the content of this article. Although we do appreciate the good intentions of the authors, we do not agree with some of the particulars mentioned. We also found certain sections of the article to be quite objectionable and irrelevant. We were disturbed by the implication that prenatal diagnostic techniques are being predominantly used for fetal sex determination in our country. The statement “the Indian medical profession actively promoted it [prenatal diagnosis] for this purpose [prenatal sex selection]” is not only offensive but also untrue, and it portrays the entire medical community of India in a very bad light. Although a very small number of medical professionals might have individually encouraged the use of prenatal diagnostic technology for prenatal sex selection when it was first introduced, the Indian medical community, as a whole, has never endorsed this. The Pre-conception and Prenatal Diagnostic Techniques (Prohibition of Sex Selection) Act of 1994 of the Parliament of India has unequivocally deemed fetal sex determination as a punishable criminal offense, and it is incorrect to generalize and blame the entire medical community for the misdemeanors of some unethical doctors who indulge in illegal practices and violate the principles of this act. Every technology has its flipside and although the misuse of prenatal diagnostic techniques cannot be denied, it has to be remembered that there are hundreds of centers across India that are using these techniques responsibly to provide reliable antenatal diagnosis of malformations and genetic disorders to innumerable affected families. Such negative statements cast a shadow on their good work. The suggestion of the authors that increasing rates of rape and other crimes against women are directly attributable to the practice of prenatal sex selection does not have any factual basis. These heinous crimes have many complex underlying sociocultural triggers, and it would be too simplistic to consider prenatal sex selection as the principal responsible factor. The authors have extensively discussed social issues such as child marriage and dowry deaths. We do not wish to downplay these extremely important sociocultural issues, but we would like to point out that these problems are not unique to India and plague many societies across the world. A discussion about them would probably be more relevant in an article about social science rather than genetic science. Moreover, references to statements such as “pay five hundred rupees now rather than five lakhs later” and “raising a girl is like watering a plant in your neighbor’s yard” seem very inappropriate for a scientific review article. There are certain factual errors in the article as well, such as the one about the society in southern India being matriarchal. The matriarchal system is followed in some communities in just one southern state of India—Kerala—and in some groups in northeastern India. Although there is a lengthy discussion of the status of women in India and the related social issues, this article does not provide any novel suggestions to address these issues. The need for strengthening enforcement of the laws against prenatal sex selection is quite well perceived by doctors, social scientists, lawmakers, and the general public of India, and necessary steps are being taken for the same. The honorable prime minister of India, referring to this issue in his Independence Day address to the country this year, has also mentioned his resolve to implement more stringent measures to check this social menace. We feel that a rather skewed picture has been presented in the article by Madan and Breuning,1 and that the authors could have provided a more balanced and scientifically relevant overview of the prenatal diagnosis scenario in India.

Utility of chromosomal microarray in five cases with cytogenetic abnormalities detected by traditional karyotype

To the Editor : Cytogenetic/cytogenomic/chromosomal microarray (CMA) using oligonucleotides to detect copy number variants (CNVs) has been recommended as first tier test in the evaluation of patients with developmental delay/intellectual disability, multiple congenital abnormalities and autistic spectrum disorders (1). Moreover, CMA can provide further information in cases with chromosomal imbalances of unknown origin. In this study, we have described five cases with cytogenetic abnormalities, in which CMA has provided useful additional information. CMA was performed by the Cytogenetics 2.7M Array, Affymertix (four cases) and HumanCytoSNPchip, Illumina (one case). GRch 37: Feb 2009 (hg 19) human genome version was used to annotate the data. Clinical details of all five cases are presented in Table 1. Various cytogenetic abnormalities included extra unidentified material on one chromosome (cases 1 and 5), cytogenetically balanced translocation (case 2), presence of a marker chromosome (cases 1, 3, and 4) and mosaicism (case 1). In two families (cases 3 and 4) CMA was performed on prenatal samples also, as conventional karyotype results were either not conclusive or to look for submicroscopic rearrangement at chromosomal breakpoints. In case 1, karyotype had shown extra material on 12p, CMA showed gain of 34 Mb in this region suggestive of tandem duplication of this segment. CMA also identified the presence of small (415 kb) loss in the same region pointing toward cryptic chromosomal rearrangement. In the same case, karyotype also showed the presence of a marker chromosome in 15/25 cells. CMA failed to detect the origin of this marker chromosome in mosaic state. Few previous studies also have pointed out that CMA may fail to detect the origin of marker chromosome in as many as >50% of cases, especially if it contains repetitive heterochromatin region which is usually not covered by probes in array platform (2). Case 2 was having cytogenetically balanced de novo translocation between chromosomes 1 and 4. However, CMA showed cryptic deletions at the break points. In case 3, karyotype of the proband showed the presence of a marker chromosome. CMA report of the proband showed double segmental imbalance involving chromosomes 11 and 22 as shown in Table 1. Karyotype of the mother showed balanced translocation between chromosomes 11 and 22. Amniocentesis and fetal karyotype was done in next pregnancy of the mother. Karyotype result was similar to mother showing the balanced chromosomal translocation. CMA in the fetal sample did not show any significant genomic gains or losses. Thus, CMA helped us in determining the accurate prognostication of the fetus. In case 4, amniocentesis was done in mother at 15 weeks of gestational age in view of previous child with Down syndrome. Fetal karyotype showed the presence of a de novo marker chromosome. CMA report showed five copy number state of 2.5 Mb region at 15q11.1-11.2. There were paucity of probes in pericentromeric region and 15p region. The involved region does not contain critical region of Prader Willi/Angelman syndrome (PWS/AS) region. Hence, it may not be associated with any clinical phenotype as described by studies in the past (3). Fluorescent in situ hybridisation (FISH) using probes for 15p11.2 and 15q11.1-13 (Vysis D15ZI and GABRB3, respectively) was performed on metaphase spread. FISH report showed two extra signals for 15p11.2 regions, located on marker chromosome (Fig. 1) thus indicating the duplication of this segment also, which was not picked up by CMA. After genetic counseling, the couple decided to continue the pregnancy. Baby was followed up at 3 months and then at 1 year and was found to be normal. In case 5, CMA identified the origin of extra chromosomal material on 12p. This implies the presence of tandem duplication of this segment. We reported five cases where an abnormal karyotype was complemented with CMA, resulting in better delineation of the genetic defect. However, it may fail to detect origin of marker chromosome or low level mosaicism if it contains mainly heterochromatin or probe coverage in concerned area is poor. Hence along with highlighting the utility of CMA in such cases;