Erica M. Bühler

Cat-eye syndrome, a partial trisomy 22

SummaryA family is presented in which a phenotypically normal mother and her healthy daughter both had abnormal children with a small supernumerary chromosome. Both had clinical symptoms suggestive of cat-eye syndrome. In both women 1 G-chromosome was found to be replaced by a small submetacentric satellited chromosome. Its fluorescence pattern was compatible with that of a chromosome 22, and so was the fluorescence pattern of the supernumerary chromosome in one of the phenotypically abnormal children. Since complete monosomy G in addition to partial autosomal trisomy would not be compatible with clinical “normality” the respective karyotypes must be interpreted as a small deletion of a chromosome 22 in the healthy mother and daughter and a partial trisomy 22 in their abnormal children. Therefore it can be concluded that a deletion of a chromosome 22 is compatible with a normal phenotype and that the cat-eye syndrome results, at least in this family, from a partial trisomy 22.ZusammenfassungEs wird über eine Familie berichtet, in der eine phänotypisch normale Mutter und ihre gesunde Tochter je ein abnormes Kind mit einem kleinen überzähligen Chromosom zur Welt gebracht hatten. Die Kinder hatten klinische Zeichen des Cat eye-Syndroms. Im Chromosomensatz beider Frauen war 1 G-Chromosom durch ein kleines submetazentrisches, satellitentragendes Chromosom ersetzt, dessen Fluorescenzumuster dem eines Chromosoms 22 entsprechen könnte. Das gleiche Muster wurde in dem überzähligen Chromosom bei einem der Kinder gefunden. Da eine totale G-Monosomie zusätzlich zu einer autosomalen Trisomie eines anderen Chromosoms nicht vereinbar ist mit vollkommener klinischer Unauffälligkeit, muß die Chromosomenanomalie der gesunden Mutter und Tochter als kleine Deletion 22 angesehen werden und die der abnormalen Kinder infolgedessen als partielle Trisomie 22. Aus diesen Befunden kann geschlossen werden, daß eine Deletion des Chromosoms 22 mit einem normalen Phänotyp vereinbar ist und daß, zumindest in dieser Familie, das Cat eye-Syndrom die Folge einer partiellen Trisomie 22 ist.

Chromosome deletion and multiple cartilaginous exostoses.

We report a 13 year-old girl with manifestations strikingly reminiscent of the tricho-rhino-phalangeal (TRP) II or Langer-Giedion syndrome. A terminal deletion of 8q must be assumed to be the cause of her condition till proven otherwise. A similar chromosome abnormality should be searched for (blindly) in other cases of the TRP II previously thought to have had normal chromosomes.

Y-body in hair roots

SummaryA method for identifying of the Y-Body in cells from hair root sheaths by fluorescent staining is described. In 52 normal males the Y-Body is found between 15 and 64%. 2 bodies were observed in 60 out of 5200 cells. In the female controls only rarely a fluorescent body was seen. The method is useful for screening tests in population genetics for identification of male sex-chromosome aberrations.ZusammenfassungEs wird über eine Methode zur Identifizierung von Y-Körperchen in Haarwurzelzellen mittels Fluorescenzfärbung berichtet. In den Zellen von 52 normalen Männern konnte das Y-Körperchen in einem Prozentsatz zwischen 15 und 64 nachgewiesen werden. 2 Y-Körperchen fanden sich unter 5200 Zellen nur 60mal. Bei normalen Frauen findet sich ein Fluorescenzkörperchen nur äußerst selten. Die Methode eignet sich für Screening-Untersuchungen zum Auffinden Y-chromosomaler Aberrationen.

Terminal or interstitial deletion in chromosome 8 long arm in Langer-Giedion syndrome (TRP II syndrome)?

SummaryReexamination with high resolution banding of the first ever published case of Langer-Giedion syndrome with 8q deletion as well as chromosome examination of a second case of this syndrome with different high resolution methods, confirmed our previous assumption of a terminal 8q involvement in the causation of TRP II syndrome.

Non-Condensation of One Segment of a Chromosome No. 2 in a Male with an Otherwise Normal Karyotype (and Severe Hypospadias)

SummaryA child with severe hypospadias is presented, whose karyotype showed in about 11% of mitoses of peripheral blood one member of chromosome pair No. 2 with a non-condensed region near the centromere. The non-condensed segment does not show late replication, however, it is situated very close to the late replicating segment of the long arms of chromosome No. 2. The nature and possible implications of this kind of aberration are discussed. It is held that non-condensation can produce localized chromosome breaks by a mechanism possibly different from any of the classical breakage mechanisms.

Trisomy 8 mosaicism - A case report and a proposed list of the clinical features

A 16-year-old boy with trisomy 8 mosaicism is presented. Increased birth weight, delayed psychomotoric and accelerated somatic development, and mental retardation were noted; he exhibited a prominent forehead, a broad-bridged upturned nose, an everted lower lip, low set dysmorphic ears, strabismus, slender trunk, narrow pelvis, osseous and joint anomalies, clinodactyly, deep skin furrows on the soles, and agenesis of the corpus callosum. The trisomic cell line was observed throughout the follow-up examinations from the fibroblast cultures between 1962 and 1973, but has disappeared from the lymphocyte culture.The clinical picture of this case is compared with the leading clinical signs and symptoms of the 25 cases with confirmed trisomy 8 so far published. A scheme is proposed in order to keep in mind the clinical picture suggesting trisomy 8.

Satellite DNA III and alkaline Giemsa staining

SummarySatellite DNA III becomes visualized by staining chromosomes with Giemsa at pH 10–12. Evidence is presented that besides the secondary constriction of chromosome 9, satellite III is contained in considerable amount in the long arms of chromosome 20, giving rise to a clearly visible secondary constriction just below the centromere. The latter finding confirms that reported by Bobrow et al. (1972).The long arms of the Y chromosome also show strong staining with alkaline Giemsa, the region of staining corresponding exactly with the intensely fluorescing area. This is interpreted as possible evidence for the presence of satellite DNA III in the distal long arms of the human Y chromosome.ZusammenfassungSatelliten-DNA III scheint durch Färbung mit Giemsa bei einem pH von 10–12 sichtbar zu werden. Außer in der Sekundärkonstriktion von Chromosom 9 ist Satelliten-DNA III in hinreichender Menge im langen Arm von Chromosom 20 vorhanden, da nach Färbung mit Giemsa-12 eine deutliche Sekundärkonstriktion sichtbar wird. Dieser Befund wurde schon von Bobrow et al. erhoben (1972).Die langen Y-Arme färben sich auch stark mit alkalischem Giemsa; die angefärbte Region stimmt genau mit dem intensiv fluorescierenden Anteil überein. Möglicherweise ist dies ein Hinweis für die Anwesenheit von Satelliten-DNA III im distalen Langarm des menschlichen Y-Chromosoms.

Q-banding of human chromosomes after BUdR and BCdR treatment

SummaryTwo different Q patterns were found in BUdR and BCdR treated chromosomes of human lymphocyte cultures: X-type pattern, in which Giemsa and quinacrine banding both are reversed; Y-type pattern, in which Q-banding remains conventional in spite of reverse G-banding. Possible mechanisms of these findings are discussed.

Banding techniques in the evaluation of human chromosomal variants

Summary6 cases of human chromosomal variants are presented as observed with different staining methods (conventional staining and banding techniques). It is concluded that the well-known variations of the short arm-satellite region of acrocentric chromosomes is mainly due to differences in length of the secondary constrictions. A review of the staining differences of chromosome regions with known polymorphisms is presented.ZusammenfassungEs werden 6 Fälle von Normvarianten menschlicher Chromosomen beschrieben, die mit verschiedenen. Färbemethoden (konventionellen und neuen banding-Methoden) untersucht wurden. Aus diesen Befunden kann geschlossen werden, daß die bekannten Variationen der Kurzarm-Satellitenregion der akrozentrischen Chromosomen hauptsächlich durch Längenunterschiede der Sekundärconstrictionen zustande kommen. Es wird ein kurzer Überblick über die Unterschiede in der Anfärbbarkeit derjenigen Chromosomenabschnitte gegeben, die bekannte Polymorphismen aufweisen.

A variant of the fra(X) syndrome

SummaryA decondensed site at band q26 of the X chromosome was found in a male baby with growth and developmental retardation and a dysmorphic syndrome, as well as in his phenotypically normal mother, without using any special culture conditions.