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A 17 year old girl was referred with a history of oligomenorrhoea. She had attained the menarche at the age of 11 years and had always had irregular periods. Over the previous 16 months, she had only two periods that were light and lasted ®ve days each.She was sexually active, used a barrier method of contraception and was nulliparous. There was no signi®-cant medical or family history. She was in good physical and mental health and was of average height and weight with a body mass index of 22. She had normal secondary sexual characteristics.An ultrasound scan of the pelvis showed a normal uterus and ovaries with a right ovarian follicle measuring 2.8 cm. Her plasma prolactin was 184mU/ L, follicle stimulating hormone was 83 iu/L, luteinising hormone was 42.2 iu/L and oestradiol was ,80 pmol/L. These levels were similar to those measured nine months earlier. Cytogenetic analysis of peripheral blood revealed an abnormal X chromosome with the following karyotype:46, X, der (X) t (X;5) (q27;p14). ish der (X) t (X;5) (wcpX1, wcp51, 210 B51, 878a7-, D5S231) ( Fig.1) Fluorescence in-situ hybridisation was carried out on a repeat blood sample to determine the nature of this abnormal X chromosome. A whole chromosome X paint hybridised to all of the normal X chromosome, to all of the short arm and approximately 75% of the long arm of the abnormal X chromosome. Use of the whole chromosome 5 paint showed that the additional material on the abnormal X was from chromosome 5. Thus the studies concluded that the abnormal X was a derived X chromosome resulting from an unbalanced translocation between an X chromosome long arm and a chromosome 5 short arm. (Fig. 2) Three months later her plasma hormone levels were: follicle stimulating hormone 30.6 iu/L; luteinising hormone 43.3 iu/L and oestradiol 189 pmol/L. This was shortly followed by a menstrual period lasting ®ve days with a moderate blood loss.A diagnosis of premature ovarian failure with an unbalanced X chromosome, with autosome translocation of the long arm of the X chromosome was made. The young woman was advised to take hormone replacement therapy. DiscussionThe criteria for diagnosis of premature ovarian failure are more than four months of amenorrhoea, with two serum follicle stimulating hormone values of .40 iu/L taken four months apart in a women less than 40 years of age. The incidence is 1 % at 40 years and 0.1 % at 30 years and decreases as age decreases 1 . The varying degrees of premature ovarian failure have been referred to as a spectrum of ovarian dysfunction ranging from ovarian dysgenesis to premature menopause 2 . Factors affecting apoptosis or programmed cell death through various phases of ovarian function from birth through to the menopause are not clearly understood, making it dif®cult to de®ne the aetiology of the vast majority of these cases. In a recent review of 323 women with premature ovarian failure the causes were 2 : Idiopathic 59%; Turner's syndrome 23%; Iatrogenic 10%; familial premature ovarian failure 4%; galactosaemia 2%; 46 XY gonadal ...

For a complete understanding of the genetic make up and genetic/breeding system of any organism it is essential to study the behaviour of chromosomes during all such processes which directly or indirectly effect the latter. These processes are i) mitosis, ii) male meiosis, iii) female meiosis and the development of the female gametophyte and iv) process of fertilization followed by the formation of the embryo. A perusal of literature clearly reveals that in the plant kingdom while as the first two (mitosis and male meiosis) and the last (fertilization and the formation of em bryo) have received the attention of many workers, the female meiosis and the development of embryo sac (through squashing) has been neglected. The main reason for the lack of data on female meiosis in plants is that this study is very dif ficult to make. However, even the little work done on the female meiosis in plants has clearly indicated the importance of making such a study before formulating any conclusions not only regarding the sum total of recombination possible in a taxon (Rhoades 1941,

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