The complete maternal mitochondrial genome of rare Chinese freshwater mussel Lepidodesma languilati (Bivalvia: Unionidae: Unioninae).

Lepidodesma languilati is considered threatened because of the influence of human activities in China. The complete F-type mitochondrial genome of L. languilati was determined in this study (GenBank accession no. KT381195). It is a 15 754-bp-long circular molecule that consists of 37 genes that are typically found in other invertebrates. The overall base composition of the entire sequence is as follows: A (39.1%), T (25.7%), C (23.4%), and G (11.8%). Except for cox1 (TTG), cob (ATT), nad1 (ATT), nad6 (ATA), nad4 (TTG), and atp8 (GTG), 7 of the 13 protein-coding genes initiate with orthodox ATG start codon. All the 13 protein-coding genes have complete termination codon TAA or TAG. Phylogenetic tree indicates that L. languilati belongs to Unioninae. The newly sequenced complete mitogenome can provide basic data for comparative studies on mitochondrial genomes of Unionidae. It could also lay the important theoretical foundation for phylogenetics, population genetics, germplasm resources protection, sustainable, and reasonable utilization.

Analysis of four fetuses with de novo chromosomal rearrangments using single nucleotide polymorphism microarray chips / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the value of single nucleotide polymophism (SNP) microarray for delineation of de novo chromosomal rearrangements detected upon prenatal diagnosis.</p><p><b>METHODS</b>SNP microarray analysis was carried out for 4 fetuses with de novo sSMCs or balanced reciprocal translocations. Genomic DNA was extracted from cord blood samples, and amplified, tagged and hybridized following the manufacturer's protocol. Data were collected and analyzed.</p><p><b>RESULTS</b>No pathogenic CNVs were detected in fetus A, whose sSMCs was verified to be heterochromatin. Fetus B, who had a de novo mosaic sSMCs, was found to have a 9 Mb duplication in 4p12-q13 which is associated with speech delay and mental retardation. No pathogenic CNVs were detected in fetus C who has 2 translocation chromosomes inherited from its mother and 2 chromosomes derived from a de novo translocation. Fetus D, who had a de novo "balanced" reciprocal translocation, was found to have a 25 Mb duplication in 1q25 and a 17 Mb deletion in 9p22. Cases A and C had normal physical and mental evaluation after birth.</p><p><b>CONCLUSION</b>For its ability to detect cryptic imbalance in de novo sSMCs or balanced reciprocal translocations, SNP-array has provided a powerful aid to conventional karyotype analysis during prenatal diagnosis.</p>