A further case with a small supernumerary marker chromosome (sSMC) derived from chromosome 1—evidence for high variability in mosaicism in different tissues of sSMC carriers

A prenatally ascertained case with a de novo small supernumerary marker chromosome (sSMC) derived from chromosome 1 is reported. Due to a fetal heart defect the parents decided in favour of an induced abortion. Postmortem, a molecular cytogenetic study on eleven formalin fixed, paraffin-embedded tissues of the fetus was performed, to further characterize the levels of mosaicism of the sSMC(1). sSMC presence varied between 13 and 62% within different tissues of sSMC carriers. This finding is something common in sSMC carriers and could explain why up to the present no clinical correlations for sSMC mosaicism and clinical outcome in the corresponding carriers could be established. Copyright © 2007 John Wiley & Sons, Ltd.     

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This study is concerned with the role and significance of "hearing out" pure tones in many types of sound. While for decades the phenomenon had played only a secondary role in auditory psychophysics, it is becoming now recognized as a key to auditory information acquisition. It is suggested that the auditory spectral pitches (i.e., the subjective pitches of pure tones) are in several respects analogous to visual contours; that both in visual and auditory perception contours convey most important information on external objects; and that contourization requires a decision process in the peripheral part of the sensory system and such can be regarded as the first step of sensory information processing. Recent experimental results on part-tone synthesis of audio signals are outlined that strongly emphasize the significance of part-tone hearing.