J Med Genet: first published as 10.1136/jmg.7.1.33 on 1 March 1970. Downloaded from Journal of Medical Genetics (1970). 7, 33.

A Deleted B Chromosome in a Mosaic Mother and her Cri du Chat Progeny J. PHILIP, N. J. BRANDT, B. FRIIS-HANSEN, M. MIKKELSEN, and I. TYGSTRUP From the Chromosome Laboratory, Department of Obstetrics and Gynaecology, the Department of Paediatrics, the Laboratory of Paediatric Pathology, Rigshospitalet, University of Copenhagen; and the Department of Obstetrics and Gynaecology, Copenhagen County Hospital, Gentofte; and the_J. F. Kennedy Institute, Glostrup, Denmark

Familial occurrence of chromosomal anomalies first concubinary she had four pregnancies, one ending may be caused by: (1) numerical chromosomal as a spontaneous abortion, one was legally interrupted, abnormalities present in all or some of the cells of and two resulted in normal children. With her second one of the parents (secondary non-disjunction), or concubinary she became pregnant twice; the first of (2) by a genetically determined tendency to meiotic these pregnancies resulted in the propositus with the or mitotic cri du chat syndrome, the second was terminated by non-disjunction. hysterotomy at four months' gestational age. At opera- Structural chromosomal abnormalities such as tion the internal genitalia were found to be normal, and translocations have also been described as frequent biopsies from the following organs were removed from causes of familial chromosomal errors. It is the the mother for chromosomal analysis: skin, muscle, purpose of this paper to report the results of chro- uterus, and right and left ovary. The fetus was dis- mosome studies in a family in which two sibs carried sected with the help of a dissecting microscope, removing a deletion of a short arm of a chromosome No. 5. tissues from skin, muscle, lung, and heart. copyright. One was a child with the typical cri du chat syn- Child drome, the other was a fetus 14 with cri du chat syndrome (propositus). weighing g. The This child, a boy, was born after an uneventful pregnancy, mother was found to be a mosaic of normal cells two weeks before term. Birthweight 2700 g. The child and cells with a deleted B chromosome. A fertile had severe asphyxia at birth with an Apgar score of 5 mosaic of this type has not been reported before. after 10 minutes, and made the first weak scream after 15

minutes. Assisted ventilation had to be given for 25 http://jmg.bmj.com/ Material and Methods minutes. The physical examination showed the typical appearance of the cri du chat syndrome: microcephaly Chromosomal analysis was carried out on cells from (head circumferance 32-5 cm.), 'rounded face', peripheral blood of a child with the cri hyper- du chat syndrome. telorism, low-set, small ears with accessory fibromas, Later the mother, her two living children, and a fetus, retromicrognathia, short neck with loose four of her five sibs, the skin, and maternal grandmother, and the simian creases of both palms. The fourth toes were father of the child with the cri du chat syndrome were displayed dorsally, and the fifth toes were both also investigated (Fig. 1). The very maternal grandfather small. The infant's cry was suggestive of the miaowing and one of the mother's sibs were dead at the time of of a cat. on September 29, 2021 by guest. Protected the investigations. A modification of the method of At follow-up examination at year age Moorhead et al. (1960) 1 of severe was used. retardation was found together with Other tissues were investigated by a modification generalized hypo- ofthe tonia. Height 70 cm., weight 7450 g., method of Harnden (1960) (Philip, 1967). and head cir- Autoradio- cumference 42 cm. The physical signs of the cri du graphic studies were performed by the method of chat Froland (1965). syndrome, including the cat cry, were still typical. Laboratory examinations. The only abnormal bio- Case Reports chemical findings were: (1) slightly decreased serum The Mother. The mother was 33 years old and un- albumin (3-92 g./100 ml.); (2) raised fetal haemoglobin married, and the father was 30, when the child with the level (59%o at the age of 6 weeks); (3) very low activity of cri du chat syndrome was born. General and gynae- beta-D-glucosidases in the urine (0-06 units at 6 weeks of cological examination of the mother, who had always age) but increasing during the next three months to enjoyed good health, showed normal findings. With her levels just below normal range of this age-group (0-295 units); and (4) moderately increased levels of amino acids in serum and urine (non-specific). The following Received 3 October 1969. parameters were all within normal range: urinary acid 3 33 J Med Genet: first published as 10.1136/jmg.7.1.33 on 1 March 1970. Downloaded from 34 Philip, Brandt, Friis-Hansen, Mikkelsen, and Tygstrup TABLE RESULTS OF CHROMOSOMAL ANALYSES

No. of Cells No. of Cells No. Tissue by < 43 43 44 45 46 47 Total Analysis Photomicro-Anslysed with Deletionof graphy* B Chromosome I.1 Blood 2 48 50 46,XX 3 0 Il.1 Blood 2 2 46 50 46,XX 5t 0 II.2 Blood 1 4 44 1 50 46,XY 9* 0 11.3 Blood 1 2 47 50 46,XX 55 0 (4 gaps, 1 frsgment) II.4 Blood I 1 2 105 2 1101 27 7 Blood II 1 9 39 1 50 10 (see text) 2 Skin 1 1 1 9 38 50 f3 (with 46) 0 (1 ?) 46,XX/46,XX,Bp - 1 3 (with 45)1 Uterus 1 1 9 4 35 501 3 0 Ovary (left) 5 2 5 4 34 50 3 1 Ovary (right) Unsuccessful J II.4B Blood 1 29 30 46,XY 3 0 II.5 Blood 1 3 46 50 46,XY 4¶ 0 (1 fragment) III.1 Blood 1 2 5 41 1 50 46,XX 3 0 III.2 Blood 1 3 5 41 50 46,XX f3 (with 46)** 0 t3 (with 45) III.5 Blood 1 2 47 50 46,XY,Bp - 3 50 (1 cell?) III.6 Skin 5 2 7 36 50 3 50 Lung 2 2 4 42 50 46,XX,Bp- 3 50 (1 cell?) Muscle 1 3 9 36 1 50J 3 50 * All counted cells have been analysed in the microscope for the deleted chromosome. t In many cells one of the D group chromosomes was clearly larger than the other D group chromosomes. t 4 cells had a long D group chromosome. § 2 cells had a long D group chromosome. 11 1: C-; 1: E-; 1: F-. !I One cell had a long D group chromosome. ** 1: A-; 1: C-; 1: F-.

mucopolysaccharides, urinary arylsulphatase A and B, which tritiated thymidine was added, were photo-copyright. serum acetylcholinesterase, serum lactic acid dehydro- graphed. The results of the autoradiography of genase, and the following erythrocyte enzymes: pyru- the B chromosome of nine of these cells are shown vate kinase, glutathione reductase, glucose-6-phosphate in Fig. 2. The deleted chromosome shows the dehydrogenase and ATP-ase. The sweat electrolytes were also normal. labelling pattern generally assumed to be typical of chromosome No. 5.

Fetus with deleted B chromosome. http://jmg.bmj.com/ The mother (II.4). In the first blood culture Patho-anatomical findings. No gross of abnormality from the mother 7 cells in metaphase out of the placenta and the umbilical cord was found. Micro- 100 same scopical examination showed small collections of neutro- analysed had the structural abnormality in a philic polymorphonuclears in the capsular decidua. B chromosome. In a second blood culture only 2 The fetus weighed 14 g., crown-rump length was 66 out of 50 cells had the Bp-chromosome; no auto- mm., and foot length 9 mm. The eyes were far set, but radiographic examination was, therefore, attempted. no other external abnormality was detected. A complete analysis was carried out in all cells By dissection, no malformation of the organs or the from the second culture with amodal numbers. In on September 29, 2021 by guest. Protected skeleton was found. Microscopical examination of the 9 of 10 cells with less than 46 chromosomes the organs revealed two anomalies: in the cortex of the kid- missing chromosomes were apparently from dif- neys a number of small cysts with flat epithelium among normally developing glomeruli and ferent groups. One cell had a 45,XX,D-GG-, proximal and distal t tubuli, and in the ovaries a reduced number of oocyto- (DqGq), and another cell had a 47,XX,G + karyo- blasts in relation to the age of gestation. type. In the other investigated tissues from the mother Results the deletion was not found, except in one cell from the left ovary. The results of the chromosomal analyses are seen in the Table. The fetus (II.6). The deleted chromosome was The present in all investigated cells from skin, lung, and propositus. The propositus (III.5) had a muscle from the fetus. deletion of the short arm of a B chromosome in all investigated cells from blood. The family. Normal karyotypes were found in Sixteen selected cells from a second culture, to cells from blood from the maternal grandmother J Med Genet: first published as 10.1136/jmg.7.1.33 on 1 March 1970. Downloaded from A Deleted B Chromosome in a Mosaic Mother and her Cri du Chat Progeny 35 (1.1), the 2 oldest children (III.1; III.2) of the mother, and in her 4 living sibs (II.1; II.2; II.3; II.5). The father (II.4B) of the child with cri du chat syndrome had a normal chromosome comple- S.. ment (Table). Discussion A deletion of the short arm of a chromosome No. 5 was found in 4-7% of cells from two blood cul- tures from the mother of a child who clinically and cytogenetically had the cri du chat syndrome. In only one cell from the left ovary of the mother the same structural abnormality was present. As she had two pregnancies where the zygote must have carried the deleted chromosome the number of ova with the deleted chromosome cannot have been negligible. The propositus and the fetus both had a deletion of the short arm of a B chromosome in all the cells investigated. The propositus was a typical example of the cri du chat syndrome. The fetus only re- vealed minor abnormalities. In a recent review of 69 cases of cri du chat syndrome Mennicken et al. (1968) stressed that in more than 50% of the cases no malformation was found except the cranio- facial dysmorphism; most of the malformations copyright. described were cardiovascular, two cases had renal abnormalities, and one case had hypospadia. The technical difficulties in the examination of a 66 mm. crown-rump fetus are obvious, and besides the "Ibeasofteanraphn.e abnormalities found, i.e. hypertelorism, slight

cystic kidneys, and retarded development of the http://jmg.bmj.com/ ovaries, other malformations may have been over- looked. Mosaicism involving either sex chromosomes or autosomes is usually found in phenotypically on September 29, 2021 by guest. Protected y~~~~~~

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3 4 5 6 III3,III4, and the children of II.1,2,3,and5 not investigated Spontaneous abortion § Legal abortion ism may, therefore, be present in the normal *Cri du chat syndrome population in higher frequencies, than is now * Legal abortion with Bp- assumed (cf. Court Brown, Jacobs, and Brunton, FIG. 1. The pedigree of the family. 1965; Sergovich et al., 1969). J Med Genet: first published as 10.1136/jmg.7.1.33 on 1 March 1970. Downloaded from 36 Philip, Brandt, Friis-Hansen, Mikkelsen, and Tygstrup Apparently normal people with mosaicism have This work was supported by the Foundation for Con- thus been ascertained because of abnormal progeny. genital Malformations, The P. Carl Petersen Foundation, Trisomy C mosaicism has been published by and the Danish State Research Foundation. Stolte, Evers, and Blankenborg (1964) and Bishun (1968) in normal mothers of abnormal children. REFERENCES Several reports have been published of women Bishun, N. B. (1968). Normal/trisomy G mosaicism in the mother having children with Down's syndrome, who them- of a 'mongoloid' child. Acta Paediatrica Scandinavica, 57, 243- selves were to mosaics 244. shown be of normal cells , Mannion, P. L., Rashas, M. N., Neely, M. R., Morton, W. R. and cells trisomic for chromosome No. 21 (Blank M., and Burke, G. (1964). Chromosomal mosaicism in a case of et al., 1963; Smith et Schade repeated abortion. Lancet, 1, 936. al., 1962; and Blank, C. E., Lord, P. Mary, Casey, M. D., and Laurance, B. M. Schoeller, 1963; Weinstein and Warkany, 1963; (1963). Chromosome mosaicism in a mongol born to a young Ferrier, 1964; Verresen, van den Berghe, and mother. Cytogenetics, 2, 76-84. Court Brown, W. M., Jacobs, P. A., and Brunton, M. (1965). Creemers, 1964). In these cases the children were Chromosome studies on randomly chosen men and women. mongols with 100% trisomic cells. Lancet, 2, 561-562. Mosaics cells Ferrier, S. (1964). Enfant mongolien-parent mosaique. J3ournal including with structural abnor- de Genetique Humaine, 13, 315-336. malities, except for translocation chromosomes, are Froland, A. (1965). Photographic recording and dye staining of rare. Mosaicism with deletion of a chromosomes for autoradiography and morphology. Stain chromosome Technology, 40, 41-43. No. 18 is reported by Lejeune et al. (1967). A Harnden, D. G. (1960). A human skin culture technique used for deletion of one of the smallest elements (22?) cytological examination. British journal of Experimental Patho- with a was logy, 41, 31-37. together 46/47 mosaic described by Kjessler, B. (1965). Karyotypes of 130 childless men. Lancet, 2, Pfeiffer, Schellong, and Kosenow (1962). Patients 493-494. with mosaics cells with a deleted Lejeune, J., Berger, R., Rethore, M.-O., Lafourcade, J., Dutrillaux, including chro- B., Canlorbe, B., and Labrune, B. (1967). Deux cas de syndrome mosome No. 5 are reported by Zellweger (1966) and 18q - en mosaique (46,XX/46,XX,18q -). Annales de Genetique, Roca et al. (1968) and a mosaic with a chromo- 10, 18-24. ring Mennicken, U., Pfeiffer, R. A., Puyn, U., Worbes, H., and Wagener, some No. 5/normal cells by Steele et al. (1966). A. (1968). Klinische und cytogenetische Befunde von 7 Patienten Warburton et al. (1969) in some cases of the cri du mit Cri-du-Chat Syndrom. Zeitschrift fUr Kinderheilkunde, 104, chat could 230-256. copyright. svndrome only show very minute dele- Moorhead, P. S., Nowell, P. C., Mellman, W. J., Battips, D. M., and tions of the short arm of the B chromosome. There- Hungerford, D. A. (1960). Chromosome preparations of leuco- fore, the authors that the cytes cultured from human peripheral blood. Experimental Cell proposed phenotype of Research, 20, 613-616. these patients was due to mosaicism, which they Pfeiffer, R. A., Schellong, G., and Kosenow, W. (1962). Chromo- were unable to demonstrate. somenanomalien in den Blutzellen eines Kindes mit multiplen Abartungen. Klinische Wochenschrift, 40, 1058-1067. Mosaics with mixtures of numerically normal and Philip, J. (1967). Kromosomstudier ved primnTr amenorrhoea abnormal cells can reproduce. Their reproductive (Thesis). University of Copenhagen. http://jmg.bmj.com/ be Roca, M., Antich, J., Ribas-Mund6, M., and Prats, J. (1968). The ability may, however, hampered. and Kjessler cri du chat syndrome with chromosome mosaicism. (Spanish) (1965) found 5 cases of mosaicism among 130 men Medicina Clinica, 50, 180-184. a clinic. Schade, H., and Schoeller, L. (1963). Schwachsinn als Symptom attending sterility bei Chromosomenanomalien. Mosaicism a Bericht uber die Tagung der Deuts- may play significant role among the chen Gesellschaft fur Anthropologie, 8, 62-66. (Supplement zu causative factors of congenital malformations and Homo: Zeitschriftfur vergleichende Forschung am Menschen.) abortions Bishun et and Sergovich, F., Valentine, G. H., Chen, A. T. L., Kinch, R. A. H., and (cf. al., 1964), the findings Smout, M. S. (1969). Chromosome aberrations in 2159 consecu- in the reported stress the tive newborn babies. New EnglandJournal of Medicine, 851- family again importance 280, on September 29, 2021 by guest. Protected of of the families in which 854. investigation congenital Smith, D. W., Therman, E. M., Patau, K. A., and Inhorn, S. L. malformations are due to chromosome abnormali- (1962). Mosaicism in mother of two mongoloids. American ties. Journal of Diseases ofChildren, 104, 534. Steele, M. W., Breg, W. R., Eidelman, A. J., Lion, D. T., and Terzakis, T. A. (1966). A B-group ring chromosome with mosaic- Summary ism in a newbornwith cri du chat syndrome. Cytogenetics, 5, The normal mother of a 419-429. phenotypically child Stolte, L., Evers, J., and Blankenborg, G. (1964). Possible trisomy with clinically and cytogenetically verified cri du in chromosome group 6-12 in a normal woman. Lancet, 2, 480- chat syndrome was found to be a mosaic 481. of normal Verresen, H., cells and cells a van den Berghe, H., and Creemers, J. (1964). Mosaic with deletion of the short arm of a B trisomy inphenotypically normal mother of mongol. ibid., 1, chromosome. The mother had another pregnancy 526-527. terminated Warburton, Dorothy, Miller, D. A., Miller, 0. J., Allderdice, P. W., by legal abortion. The fetus had also and Capoa, A. de (1969). Detection of minute deletions in human the abnormal chromosome in all cells investigated. karyotypes. Cytogenetics, 8, 97-108. In cases of congenital malformations due to Weinstein, E. D., and Warkany, J. (1963). Maternal mosaicism and chro- Down's syndrome (mongolism). Journal of Pediatrics, 63, 599- mosome abnormalities, family studies are necessary 604 for genetic Zellweger, H. (1966). Cri du chat with chromosomal rr-osaicism. counselling. Lancet,2, 57.