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Y Chromosome Long J Med Genet: first published as 10.1136/jmg.9.3.373 on 1 September 1972. Downloaded from Case Reports 373 REFERENCES Short Y chromosomes have been found in normal Allerdice, P., Miller, 0. J., Miller, D. A., Breg, W. R., Gendel, E., fertile males et as as and Zelson, C. (1971). Familial translocation involving chromo- (Borgaonkar al, 1969) well in somes 6, 14, and 20 identified by quinacrine fluorescence. Human- families with diminished fertility (Muldal and genetik, 13, 205-209. Ockey, 1962). Large deletions of the Y resulting in Breg, W. R. (1972). Quinacrine fluorescence for identifying meta- phase chromosomes, with special reference to photomicrography. a fragment-like chromosome have been described in Stain Technology, 47, 87-93. an intersex raised as a female (Lo and Kobernick, Breg, W. R., Miller, 0. J., Miller, D. A., and Allerdice, P. W. (1972). Identifications of reciprocal translocation chromosomes 1965), in a Turner's syndrome patient where it by quinacrine fluorescence. American Journal of Diseases of occurred with 45,X mosaicism (Ferguson-Smith Children, 123, 561-564. et al, 1969), and in a retarded male Br0gger, A. (1967). Translocations in Human Chromosomes, p. 110. severely baby Universitets Forlaget, Oslo. (Nakagome et al, 1965). The case presented here Caspersson, T., Lomakka, G., and Zech, L. (1971). The 24 fluores- is apparently the first in which an extreme deletion cence patterns of the human metaphase chromosomes-distinguish- ing characters and variability. Hereditas, Genetiskt Arkiv, 67, 89- of the Y chromosome was found to be associated 102. with fertility as well as normal male development. Chicago Conference: Standardization in Human Cytogenetics (1966). Birth Defects: Original Article Series, II, 2. The National Foundation-March of Dimes, New York. Ford, C. E. and Clegg, H. (1969). Reciprocal translocations. Case Report British Medical Bulletin, 25, 110-114. Giannelli, F. (1965). Autoradiographic identification of the D (13- Chromosome studies were done on a 36-year-old 15) chromosome responsible for D1 trisomic Patau's syndrome. mentally-retarded male (IQ 51), with several minor Nature, 208, 669-672. physical anomalies. He is 179 cm tall, with a normal Hauschteck, E., Murset, G., Prader, A., and Biihler, E. (1966). Sib- male habitus, including heavy beard and normal external lings with different types of chromosomal aberrations due to D/E- translocation of the mother. Cytogenetics, 5, 281-293. genitalia. During childhood, he had surgery for bi- Jacobsen, P., Dupont, A., and Mikkelsen, M. (1963). Translocation lateral inguinal hernia and undescended testicles, but his in the 13-15 group as a cause of partial trisomy and spontaneous testicles are now of normal adult size. He usually abortion in the same family. Lancet, 2, 584-585. Miller, D. A., Allerdice, P. W., Miller, 0. J., and Breg, W. R. (1971). speaks with a peculiar high-pitched voice, but is capable Quinacrine fluorescence patterns of human D group chromosomes. of using deep voice tones on occasion. His chest Nature, 232,24-27. shows pseudo-gynaecomastia, no true breast tissue being Miller, J. R., Dill, F. J., Corey, M. J., and Rigg, J. M. (1970). A present. rare translocation - (47,XY,t(2p ;21q + ),21 +) associated with copyright. Down's syndrome. Journal ofMedical Genetics, 7, 389-393. The shape of the head is remarkably round, with a Murken, J. D., Bauchinger, M., Palitzsch, D., Pfeifer, H., Suschke, bilateral frontal-temporal depression and a low anterior J., and Haendle, H. (1970). Trisomie D2 bei einem 21 jihrigen hairline. The eyes appear deeply set, and he wears Madchen (47,XX,14 +). Humangenetik, 10, 254-268. Patau, K., Smith, D., Therman, E., Inhorn, S., and Wagner, H. P. glasses for severe myopia. Brushfield spots are noted (1960). Multiple congenital anomaly caused by an extra auto- in the iris periphery. There is anteversion of both some. Lancet, 1, 790-793. auricles, and the chin is prominent. Acne extends from Taylor, A. (1968). Autosomal trisomy syndromes: a detailed study his to of 27 cases of Edwards' syndrome and 27 cases of Patau's syn- shoulders the upper portions of his chest and back. drome. Journal of Medical Genetics, 5, 227-252. In addition, he has numerous small, bright-red cavernous Taylor, M. B., Juberg, R. C., Jones, B., and Johnson, W. A. (1970). haemangiomas on the neck, arms, and scalp. Examina- Chromosomal variability in the D1 trisomy syndrome. American tion of the extremities shows hypoplasia of the 5th meta- http://jmg.bmj.com/ Journal of Diseases ofChildren, 120, 374-381. carpals, resulting in short-appearing 5th fingers. The big toes are short and slightly clubbed, and all of the finger and toenails are strikingly short in length. The patient, the youngest of4 children, was born when his mother was 32 years old. His sisters, now aged 44 and 42, have had 2 and 3 children respectively, while kis 43-year-old brother has 4 children. All of his sibs and their children are normal. Normal Male Development with on October 5, 2021 by guest. Protected Y Chromosome Long Arm Cytogenetic Studies Deletion (Yq-)* Chromosome studies from a peripheral blood culture showed a karyotype of 46 chromosomes, all Many observers have reported the variability in Y of which appear normal with the exception of what chromosome length and the apparent lack of any is presumed to be the Y (Fig. 1). This is a small phenotypic effect attributable to a very long Y. metacentric chromosome, less than half the size of the G Received 20 March 1972. other chromosomes. When stained with * This work was partially funded through an agreement with the quinacrine, no brightly fluorescent region attribut- Wisconsin Division of Health by the Children's Bureau, Department able to the Y chromosome was seen (Figs. 2 and 3). of Health, Education, and Welfare. This report was presented at the Tenth Annual Somatic Cell Genetics Conference in Aspen, Colorado, A buccal smear stained with quinacrine showed no 18-20 January 1972. fluorescing Y bodies. J Med Genet: first published as 10.1136/jmg.9.3.373 on 1 September 1972. Downloaded from 374 Case Reports .,,,,. ,# '.... * :^,{,4414) :.' 1"1 tf 11x ,\ i. AC is*. AR .._,;;,. .: *W.). .. 9, I.-- 1 *' 4 *l..-.S . ....... @e :S0W 6* 10 IdR FIG. 1. Karyotype ofthe patient, showing the deleted Y. copyright. http://jmg.bmj.com/ on October 5, 2021 by guest. Protected FIG. 2. Patient's fluorescent metaphase cell, stained with quinacrine dihydrochloride ( x 2000). Note the pale, tiny metacentric Y. J Med Genet: first published as 10.1136/jmg.9.3.373 on 1 September 1972. Downloaded from Case Reports 375 FIG. 3. Karyotype of fluorescent cell shown in Fig. 2. copyright. Because of these unexpected findings, chromo- It is not possible to determine whether the abnor- some analysis was done on blood from his pheno- mal Y chromosome arose through a simple deletion typically-normal older brother (height 179 cm), and of the Y (Yq -) or whether it is an isochromosome a morphologically similar karyotype, with a tiny of the short arm (Ypi). Both interpretations are non-fluorescing Y, was found. Neither his normal consistent with the observed morphology. If the brother nor the patient displayed metaphase plates aberration were an isochromosome of the Y short with unusual fluorescing regions in any of the auto- arm, this would prove that the long arm is devoid of http://jmg.bmj.com/ somes that could suggest a translocation of Y long any significant male-determining genes or fertility arm material. As is shown in Fig. 4, the aberrant Y factors. Furthermore, if the abnormal Y in the is approximately 1 micron in length and very meta- present case were an isochromosome of the short centric. arm, the patient as well as his normal brother and father would have 2 doses of the genetically-signifi- Discussion cant part of the Y, and would therefore be expected The fact that the patient demonstrates normal to show features of the XYY syndrome. Although on October 5, 2021 by guest. Protected male somatic development and is of average height, the range of phenotypic variation associated with the despite such an extensive long arm Y deletion, XYY karyotype is not sufficiently well-established indicates that most of the long arm, including the to make any such determination on physical findings fluorescent portion of the Y chromosome, is not alone, it is of interest to note that the patient does necessary for male development. This observation display a number of characteristics that were de- is strengthened because his older brother, with a scribed in an XYY case by Voorhees et al (1970) eg, similar deleted Y, is normal and fertile. It would acne, a low anterior hairline, gynaecomastia, and seem reasonable to assume that the missing Y shortened 5th finger. He also manifested the chromosomal material is not the cause of the mental undescended testes so commonly found in child- retardation observed in the propositus, and also that hood XYY cases (Court Brown, 1968). Despite a major Y deletion is consistent with normal fertility these XYY characteristics which support the possi- since the brother and father, who must have had the bility that we may be dealing with a Y short arm same deleted Y, both had 4 children. isochromosome, it is not possible to discriminate J Med Genet: first published as 10.1136/jmg.9.3.373 on 1 September 1972. Downloaded from 376 Case Reports 't,~~~~~~~~~~~~~~~~~~~~~. h' i' FIG. 4. Partial karyotypes of the G chromosomes with the minute Y, taken from the patient (left) and his normal brother (right). with certainty between a Ypi or Yq - on cyto- small pericentromeric portion of the Y short arm logical or clinical grounds.
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