No abstract

In the present study, we obtained population genetic data and forensic parameters of 30 InDel loci in Chinese Xibe ethnic group from northwestern China and studied the genetic relationships between the studied Xibe group and other reference groups. The observed heterozygosities ranged from 0.1704 at HLD118 locus to 0.5247 at HLD92 locus while the expected heterozygosities ranged from 0.1559 at HLD118 locus to 0.4997 at HLD101 locus. The cumulative power of exclusion and total probability of discrimination power in the studied group were 0.9867 and 0.9999999999902 for the 30 loci, respectively. Analyses of structure, PCA, interpopulation differentiations and phylogenetic tree revealed that the Xibe group had close genetic relationships with South Korean, Beijing Han and Guangdong Han groups. The results indicated that these 30 loci should only be used as a complement for autosomal STRs in paternity cases but could provide an acceptable level of discrimination in forensic identification cases in the studied Xibe group. Further studies should be conducted for better understanding of the Xibe genetic background.

The aim of this study was to investigate allelic frequency distribution and forensic genetic parameters of autosomal short tandem repeats (STR) loci of the population samples from 107 Tujia individuals from Chinese Hubei Province. Twenty-one autosomal STR genetic markers (D9S1122, D6S474, D6S1017, D5S2500, D4S2408, D3S4529, D2S441, D2S1776, D22S1045, D20S482, D1S1677, D1S1627, D1GATA113, D19S433, D18S853, D17S1301, D11S4463, D12ATA63, D10S1248, D10S1435 and D14S1434) were simultaneously amplified in a new multiplex polymerase chain reaction system. 155 alleles for all the STR loci from the Tujia population were observed and the corresponding allelic frequencies ranged from 0.005 to 0.589. Expected heterozygosity, polymorphic information content, power of discrimination and power of exclusion of the 21 STR loci in the Tujia population were from 0.579 to 0.824, from 0.525 to 0.802, from 0.773 to 0.945 and from 0.257 to 0.641, respectively. Our results indicate that the autosomal STRs multiplex system provides highly informative STR data and could be useful in forensic individual identification and parentage testing in this region.

Objective: To evaluate computed tomography (CT) and magnetic resonance imaging (MRI) features in patients with diastematomyelia and to investigate clinical characteristics of this lesion. Study design: A retrospectively study. Setting: The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University. Methods: A total of 82 diastematomyelia cases were retrospectively studied. All the patients underwent neurological examinations as well as MRI and CT of the spine. A self-established neurological functional grading system was used, and posterior tibial nerve somatosensory cortical-evoked potential (PTNSCEP) was measured to assess the neurological status of the patients. Imaging features of symmetry of splitting, presence of septum, location of lesion and number of split segments were studied. The neurological functional grading, PTNSCEP, and imaging findings were then analyzed and compared, and the difference was considered to be significant if P-value was lower than 0.05. Results: Neurological functional grading and latency of PTNSCEP were significantly different but related in terms of symmetry of splitting, presence of septum and location of lesion. Although no significant differences were present in the number of split segments, the severity of the neurological functional grading and PTNSCEP impairment were not related to the number of split segments. INTRODUCTIONDiastematomyelia is an uncommon congenital malformation of the vertebral axis where the spinal cord is split longitudinally into two. Each hemicord contains a central canal and a set of dorsal and ventral horns and nerve roots. The precise etiology is not known. The clinical manifestations include cutaneous abnormality overlying the spine, neurologic deficits and orthopedic abnormalities. [1][2][3][4] Clinically, the symptomatology is not specific and does not differ from that seen in other forms of spinal dysraphism. [5][6][7][8] Despite its low incidence, diastematomyelia results in severe neurological dysfunction. The clinical diagnosis and treatment of the lesion are therefore important. Delayed or improper treatment due to incorrect diagnosis may lead to the worsening of neurological symptoms. Conventionally, diagnosis of diastematomyelia is based on its clinical manifestations and radiological examination. Plain radiography and myelography have traditionally been used. With the improvement in imaging technology, computed tomography (CT) and magnetic resonance imaging (MRI) are established as the primary diagnostic strategies for evaluating the symptoms of diastematomyelia. Although CT and MRI findings of diastematomyelia have been discussed in the literature, 9-11 there are few reports concerning the characteristic imaging and the clinical manifestations. 12,13 The relationship between the clinical severity of diastematomyelia and the morphological changes reflect in imaging findings has never been thoroughly investigated.

No abstract