Diagnosis of an uncertain karyotype and mentally retarded child using the whole genome microarray scanning technique / 临床儿科杂志

Objective To investigate the possibility and feasibility of the whole genome microarray scanning technique in clinical cytogenetic diagnosis of an uncertain karyotype and mentally retarded child. Methods The karyotype analysis of the mental development delayed child was 47, XY+mar. Genomic DNA was extracted from the peripheral blood and the whole genome microarray scanning technique was used to analyze the derivative chromosome. Results The whole genome microar-ray scanning technique indicated the derivative chromosome fragment had originated from 9p13.1-p24.3. Conclusions Com-paring to conventional cytogenetic analysis methods, the whole genome microarray scanning technique is of high resolution, high-throughput and high accuracy, which can detect the submicroscopic chromosomal aberrations and replace the conven-tional karyotype analysis.

Dandy-Walker malformations in a case of partial trisomy 9p (p12.1→pter) due to maternal translocation t(9;12)(p12.1;p13.3).

We describe a five-year-old proband presented with Dandy-Walker malformations, right microopthalmia, hamstring contractures, undescended testis with absence of testis in right scrotum in addition to typical trisomy 9p clinical features. Routine cytogenetic studies with GTG - banding showed 46,XY,der(12)t(9;12) (p12;q13.3),mat karyotype (trisomy 9p). Chromosomal analysis of the father was normal and phenotypically normal mother had 46,XX,t(9;12)(p12;q13) karyotype. Fluorescence in situ hybridization analysis with single copy probes bA5OIA2 (9p11.2), bA562M8 (12p12.1) and centromere probes (9) showed break point at 9p12.1 region. The gene dosage effect of Chromosome 9p along with environmental factors might be associated with Dandy- Walker malformations in the patient.

A Case of Partial Trisomy 9p Syndrome with 3-Ketothiolase Deficiency / 대한소아신경학회지

Trisomy 9p syndrome was first described by Rethore et al in 1970 and about 150 cases have been reported. The characteristic features of the partial trisomy 9p syndrome is clearly recognizable faces, which include microcephaly, facial deformities, skeletal and dermatoglyphic anomalies with variable degrees of mental retardation. The 3-ketothiolase deficiency was first described in 1971 and about 30 cases have been reported. The 3-ketothiolase deficeiency is an inborn error of isoleucine and ketone body catabolism that shows autosomal recessive traits, caused by a deficiency of mitochondrial acetoacetyl-coenzyme A thiolase(T2). We report a case of partial trisomy 9p syndrome with 3-ketothiolase deficeiency in a 4-years-old female. The karyotype of the patient was confirmed as 46,XY, add(9)(p23) mat. In the urine organic acid test, 3-ketothiolase deficiency was reported.

A Case of Partial Trisomy 9 by Balanced Maternal Translocation

Trisomy 9p syndrome was first described by Rethore et al in 1970 and about 100 cases have been reported since. The phenotypic spectrum of this syndrome is characterized by craniofacial malformation, facial deformity, skeletal and dermatoglyphic anomalies with variable degrees of mental retardation. We experienced a case of partial trisomy 9 syndrome in a 15-month-old female who had multiple congenital anomalies of frontal bossing, oblique antimongoloid palpebral fissures, enophthalmos, hypertelorism, globular prominent nose, down-turned mouth, prominent low-set ears, simian creases of both hands, clinodactyly and single crease of 5th finger, congenital dislocation of both knees and mental retardation. In cytogenetic studies using G banding technique and fluorescent in situ hybridization(FISH), she presented with an extra derivative chromosome No. 9. The karyotype of the patient was confirmed as 47,XX,+der (9),t (6:9) (q27;q21.2) mat. We report the case with the review of the associated literatures.