RESUMEN
<p><b>OBJECTIVE</b>To confirm the genetic diagnosis of two patients with ring chromosome 22 syndrome and investigate the mechanism underlying the formation of r(22) and potential genetic causes for the clinical phenotypes.</p><p><b>METHODS</b>Cytogenetic and molecular analyses using standard G-banding, fluorescence in situ hybridization and single nucleotide polymorphism array (SNP array) were performed.</p><p><b>RESULTS</b>For case 1, the karyotype was 46,XY,r(22)(p11q13). SNP array has identified a 7.0 Mb heterozygous deletion at 22q13.2q13.33. For case 2, the karyotype was 46,XY,r(22)(p11q13)[84]/45,XY,-22[6]; SNP array has detected a heterozygous microdeletion of 1.6 Mb at 22q13.33.</p><p><b>CONCLUSION</b>With combined application of genetic testing, 2 cases of r(22) syndrome were diagnosed, which has improved the understanding of the genotype-phenotype correlation of r(22).</p>
Asunto(s)
Preescolar , Humanos , Masculino , Bandeo Cromosómico , Cromosomas Humanos Par 22 , Genética , Pruebas Genéticas , Proteínas del Tejido Nervioso , Genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Cromosomas en AnilloRESUMEN
<p><b>OBJECTIVE</b>To identify the small supernumerary marker chromosomes (sSMC) and guide the genetic counseling and medical treatment in two patients with Turner syndrome.</p><p><b>METHODS</b>High resolution GTG and C banding, SRY amplification by PCR and fluorescence in situ hybridization (FISH) on metaphase chromosomes were performed to the two patients.</p><p><b>RESULTS</b>The karyotypes of the two patients were 45, X [29]/46,X, +mar[31] and 45,X[71]/46,X, +mar[29] respectively. SRY test indicated SRY-positive for patient 1, whose sSMC was originated from chromosome Y. The karyotype was confirmed as 45,X[29]/46,X,idic(Y)(q10)[31]. ish idic(Y)(q10)(RP11-115H13x2) (SRY+) by FISH. While in patient 2, the sSMC was originated from chromosome X, whose karyotype was determined as 45, X[71]/46,X, r(X)(p11.23q21)[29]. ish r(X) (p11.23q21)(AL591394.11xAC092268.3).</p><p><b>CONCLUSION</b>Using cytogenetic and molecular cytogenetic analyses, we have identified the sSMCs in two patients with Turner syndrome, which was helpful to the clinical diagnosis and treatment.</p>