Chromosomal abnormalities are a very common cause of spontaneous miscarriage. Most commonly a child with a chromosomal abnormality will not survive to birth. However, there are many cases where the…
Klinefelter's syndrome is the presence of an extra X chromosome in males to give (47,XXY). Sometimes it may also be (48, XXYY) or (49, XXXY). Occasionally there is mosaicism with some cells…
Introduction Mendelian inheritance is a term sometimes used to describe patterns of inheritance, based on the original ideas of dominant and recessive genes, first proposed by the Gregorian Monk Mendel.…
Introduction In this condition there is only one X chromosome in the female. Epidemiology 95% of cases result in spontaneous miscarriage Present in 1 in 5000 Clinical features Vary widely…
Approximately 0.1% of females have an extra X chromosome. It is likely that there will be no clinical features, however, some studies suggest that: intelligence is typically reduced by 10-20…
Very similar to XXX in females. The incidence is again about 1 in 1000. They may have slightly reduced intellectual ability (10-20 IQ points), and a tendency for aggressive and…