作者: Carolyn Trunca , John M. Opitz , Celia I. Kaye
关键词:
摘要: Cytogenetic analysis after conventional staining and Q-banding demonstrated a pericentric inversion of chromosome 14 in the mother child with mental retardation/multiple congenital abnormality syndrome an abnormal 14. The proposita's partial duplication for distal segment 14q is apprently result crossing over within inverted during meiosis. An attempt made at assessing risk that carrier described faces having child. estimate depends on two factors: 1) probability crossover occurring meiosis, 2) either possible unbalanced recombinant chromosomes being born alive. explanation offered as to why some inversions confer signifcant while others are so benign occur such high frequency they can be considered normal chromosomal variants, rather than aberrations.