Twins

This morning Anna Maria Tremonti, the excellent host of the CBC Radio current affairs and documentary program, The Current, had a fascinating half hour feature on twins. The emphasis was on some of the curious and interesting behavioural qualities that have been observed in identical twins. There's a podcast at cbc.ca/thecurrent.

I got interested in twins about 60 years ago when I was in general practice in Adelaide in the late 1950s. I had two sets of elderly identical twins among my patients. One set was a pair of old men, widowers, who moved in together after both their wives died. Both had caring middle-aged children who looked after them very well, although I got the impression that they'd have coped fine even without the way their daughters, sons and grandchildren lavished meals and loving care upon them. They were fun-loving old rascals, an inexhaustible source of off-colour jokes. They both smoked like stoves and loved a drink at the end of the day which they usually spent in their large vegetable garden. They looked set to live forever.  It was heart-warming to see how they cared for each other and their many progeny. Their only complaint - the same for both - was severe arthritis which was limiting their capacity to care for their garden. They weren't fussy about dressing alike, but shared a carefree willingness to be filthy dirty.

The other pair of twins were old maids, spinsters who had lived together all their lives. To say they disliked each other is an understatement. They detested each other. I never explored the reasons for this but I got the impression that it began with mutual irritation and escalated over the years and decades. They were in their 70s when I first met them and I was intrigued to see that despite their obvious mutual dislike, expressed in vicious comments and whining complaints to me about their twin sister's innumerable faults, they dressed in identical blouses and skirts, had identical hairdos, wore identical shoes that I thought were probably interchangeable with each other. Their diseases weren't identical, however: One of these twins had high blood pressure and heart disease, the other had breast cancer.  

Not long after my acquaintance with these two sets of twins ended, Wendy and I and our kids spent a year in London in 1961-62, during which we saw a BBC TV feature about the identical twin test cricketers Alec and Eric Bedser. I learnt for the first time that there were two kinds of identical twins, collateral twins, both stamped from the same mold, so to say, and mirror image twins, one right-handed the other left-handed, one with clockwise whorls on finger prints and hair parting, the other counter-clockwise (and also subtle and unmistakeable chromosomal differences). The Bedser twins were mirror images - that one was right-handed and the other left-handed first brought this interesting fact to light.     Until an observant cricket lover looked closely at the Bedser twins, these odd facts about identical twins had never been noticed. I wish I'd noticed whether my two sets of twins were mirror image or collateral but alas, in the careless way one overlooks obvious but seemingly irrelevant clinical details, I never had.  Would identical arthritis in both twins be associated with mirror image or collateral twinning? Would cancer in one twin and heart disease in the other be associated with mirror image or collateral twinning? By now, perhaps, someone knows the answer. Maybe I would have sixty years ago if I'd been more alert and observant.

Long after we'd left Australia I found out during a return visit that I was one of twins, the other of whom was stillborn. I learnt this from an old lady I met, who had been a young nurse in the hospital in Tailem Bend, South Australia, where I was born.  My mother was dead by the time I learnt this, so I wasn't able to ask her to confirm it. She may never have known anyway, because she had severe toxaemia of pregnancy, was very ill and recalled little of the events late in her pregnancy and even less of the actual birth. I don't know whether I was the survivor of a pair of identical or fraternal (non-identical) twins, but there is a rather strong tendency to fraternal twin births in my family tree.