Summary
The fragile site at Xq27 which is associated with X-linked mental retardation with macroorchidism has been studied in 21 retarded males. These males were from 12 families, and studies of nine of the families were possible. Detection of carrier females is difficult, especially with increasing age. The fragile site was demonstrated in only five of 13 obligate carrier females. It is concluded that using present methods, cytogenetic detection of carriers is fairly reliable in females aged less than 20–25 years but unreliable in older females.
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References
Giraud, F., Ayme, S., Mattei, J. F., Mattei, M. G.: Constitutional chromosomal breakage. Hum. Genet. 34, 125–136 (1976)
Harvey, J., Judge, C., Wiener, S.: Familial X-linked mental retardation with an X chromosome abnormality. J. Med. Genet. 14, 46–50 (1977)
Howard-Peebles, P. M., Stoddard, G. R., Mims, M. G.: Familial X-linked mental retardation, verbal disability, and marker X chromosome. Am. J. Hum. Genet. 31, 214–222 (1979)
Lubs, H. A.: A marker X chromosome. Am. J. Hum. Genet. 21, 231–244 (1969)
Mulcahy, M. T.: Carrier detection in X-linked mental retardation. Med. J. Aust. 2, 489 (1978)
Sutherland, G. R.: Fragile sites on human chromosomes: Demonstration of their dependence on the type of tissue culture medium. Science 197, 265–266 (1977a)
Sutherland, G. R.: Marker X chromosomes and mental retardation. N. Engl. J. Med. 296, 1415 (1977b)
Sutherland, G. R.: Carrier detection in X-linked mental retardation. Med. J. Aust. 2, 624 (1978)
Sutherland, G. R.: Heritable fragile sites on human chromosomes. I. Effect of composition of culture medium on expression. Am. J. Hum. Genet. 31, 125–135 (1979a)
Sutherland, G. R.: Heritable fragile sites on human chromosomes. II. Distribution, phenotypic effects and cytogenetics. Am. J. Hum. Genet. 31, 136–148 (1979b)
Sutherland, G. R., Ashforth, P. L. C.: X-linked mental retardation with macro-orchidism and the fragile site at Xq27 or 28. Hum. Genet. 48, 117–120 (1979)
Sutherland, G. R., Judge, C. G., Wiener, S.: Familial X-linked mental retardation with an X-chromosome abnormality and macro-orchidism. J. Med. Genet. (in press, 1979)
Turner, G., Gill, R., Daniel, A.: Marker X chromosomes, mental retardation and macro-orchidism. N. Engl. J. Med. 299, 1472 (1978a)
Turner, G., Gill, R., Daniel, A.: Carrier detection in X-linked mental retardation. Med. J. Aust. 2, 624 (1978b)
Wiener, S., Judge, C.: Carrier detection in X-linked mental retardation. Med. J. Aust. 1, 128 (1979)
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Sutherland, G.R. Heritable fragile sites on human chromosomes. Hum Genet 53, 23–27 (1979). https://doi.org/10.1007/BF00289445
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DOI: https://doi.org/10.1007/BF00289445