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The central nervous system is derived from the neural plate, which undergoes a series of complex morphogenetic events resulting in formation of the neural tube in a process known as neurulation. The cellular behaviors driving neurulation in the cranial region involve forces generated by the neural tissue itself as well as the surrounding epithelium and mesenchyme. Of interest, the cranial mesenchyme underlying the neural plate undergoes stereotypical rearrangements hypothesized to drive elevation of the neural folds. As the neural folds rise, the hyaluronate-rich extracellular matrix greatly expands resulting in increased space between individual cranial mesenchyme cells. Based on inhibitor studies, expansion of the extracellular matrix has been implicated in driving neural fold elevation; however, because the surrounding neural and epidermal ectoderm were also affected by inhibitor exposure, these studies are inconclusive. Similarly, treatment of neurulating embryos with teratogenic doses of retinoic acid results in altered organization of the cranial mesenchyme, but alterations in surrounding tissues are also observed. The strongest evidence for a critical role for the cranial mesenchyme in neural fold elevation comes from studies of genes expressed exclusively in the cranial mesenchyme that when mutated result in exencephaly associated with abnormal organization of the cranial mesenchyme. Twist is the best studied of these and is expressed in both the paraxial mesoderm and neural crest derived cranial mesenchyme. In this article, we review the evidence implicating the cranial mesenchyme in providing a driving force for neural fold elevation to evaluate whether there are sufficient data to support this hypothesis. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We have detected, in three unrelated eastern Indian individuals, a hitherto unreported alpha zero deletion, - -KOL, in the heterozygous state, encompassing the embryonic zeta2-globin and the duplicated alpha-globin genes extending from c. 1150 bp upstream of the zeta2 globin gene to c. 960 bp downstream of the theta1 gene. Other deletions present in 120 unrelated, eastern Indian, putative alpha-thalassaemia patients are −3·7 kb (16·25%), −4·2 kb (5%) and - -SEA (3·33%). [ABSTRACT FROM AUTHOR]

Haemoglobin (Hb) Sun Prairie (α2-globin cd130,CT→CT, Ala→Pro) is detected in three unrelated chromosomes, in association with a C→T transition in the 5′-untranslated region (UTR), two bases upstream from the translation start site. Reported inversion ofα/β-mRNA ratio observed in Hb Sun Prairie mutants might stem from the second mutation and should be investigated. Molecular modelling studies indicate that the 130th residue ofα-globin faces primarily the central cavity of the molecule and is not in contact with anyβ-chain residue; further, no significant disruption of the Hb structure because of the Sun Prairie mutation is discernible. Depression of translation because of the second mutation of a conserved base in the 5′-UTR might explain the observed clinical severity. [ABSTRACT FROM AUTHOR]

Objective To control the birth of thalassemic children in India. Methods Mutations present in the population of eastern India and in carrier parents seeking prenatal diagnosis were detected by the PCR-based technique of ARMS (amplification refractory mutation system) or gap-PCR. To screen for maternal tissue contamination in CVS, haplotypes associated with the β-globin gene clusters were constructed using six polymorphic restriction sites. Prenatal diagnosis was accomplished by checking presence of parental mutation in the DNA from chorionic villus sampling (CVS) collected at 8 to 10 weeks' gestation by appropriate technique. Results Six hundred and fifty (650) unrelated β-thalassemia chromosomes were screened for 11 common mutations to characterize the mutation distribution in this population. Starting from early 2000, 63 families from different parts of West Bengal and from surrounding areas have been offered prenatal counseling for β-thalassemia. Conclusion The population of this region is conscious and willing to accept prenatal diagnosis as a means of control of thalassemia. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]