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Biometric analysis of the multiple maternities in Finland, 1881-1990, and in Sweden since 1751.

https://arctichealth.org/en/permalink/ahliterature64820
Source
Hum Biol. 1993 Jun;65(3):463-79
Publication Type
Article
Date
Jun-1993
Author
J O Fellman
A W Eriksson
Author Affiliation
Population Genetics Unit, Folkhälsan Institute of Genetics, Helsinki, Finland.
Source
Hum Biol. 1993 Jun;65(3):463-79
Date
Jun-1993
Language
English
Publication Type
Article
Keywords
Birth Rate - trends
Comparative Study
Finland
Humans
Linear Models
Maternal Age
Sweden
Triplets - statistics & numerical data
Twins - statistics & numerical data
Abstract
Hellin's law states that if the twinning rate is w, then the triplet rate is w2, the quadruplet rate is w3, and so forth. The opinion of today is that Hellin's law holds only approximately. In this study the inaccuracy of Hellin's law is studied and the discrepancies are explained mathematically. In our earlier studies we built linear models for the twinning rate. Because most of the mothers are younger than 40 years of age and because in this age interval the twinning rate depends linearly on age, linear regression methods have been applied. Hellin's law suggests using the square-root transformation of the triplet rate r. Statistical arguments speak in favor of using the arcsin square root of r transformation. We discuss both transformations. Despite the fact that Hellin's law is only approximate, the arcsin transformation proves valuable. The transformed triplet rate can be modeled in a way similar to the twinning rate. We consider secular data from Finland for 1881-1990 and from Sweden since 1751. Using Hellin's law, we compare the triplet rates and the twinning rates and study the time trends of the observed twinning and triplet rates. The data are standardized. Our theoretical results are applied to multiple maternity data for Finland. Using maternal age as the regressor, we build a linear model for the twinning rate and for the arcsin-transformed triplet rate. This analysis shows a decreasing linear time trend in the triplet series for the period 1881-1950 but not in the twinning series. The triplet rate has an increasing trend after 1960, which seems to be mainly caused by artificial induction of ovulation.
PubMed ID
8319944 View in PubMed
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Founder effect and genetic disease in Sottunga, Finland.

https://arctichealth.org/en/permalink/ahliterature232263
Source
Am J Phys Anthropol. 1988 Nov;77(3):335-46
Publication Type
Article
Date
Nov-1988
Author
E. O'Brien
L B Jorde
B. Rönnlöf
J O Fellman
A W Eriksson
Author Affiliation
Department of Human Genetics, University of Utah School of Medicine, Salt Lake City 84132.
Source
Am J Phys Anthropol. 1988 Nov;77(3):335-46
Date
Nov-1988
Language
English
Publication Type
Article
Keywords
Finland
Gene Frequency
Genetic Diseases, Inborn - genetics
Genetics, Population
History, 18th Century
History, 19th Century
History, 20th Century
Humans
Inbreeding
Pedigree
Probability
Abstract
Pedigree data are analyzed in order to determine the factors responsible for the high frequencies of certain genetic disorders in an isolated Swedish-speaking population of Finland's A land archipelago. The founders of Sottunga are identified, and the genetic contributions of each founder to descending birth cohorts are estimated. Founders born before 1700 have far more descendants in the contemporary gene pool than do more recent founders. However, because of migration and depopulation since 1900, the expected genetic contributions of the early founders to the present-day population are similar to those of later founders. A descendant in the contemporary population has a 2% chance of having inherited a particular gene from the founder who makes the largest single contribution to the gene pool. This corresponds approximately to a 2% probability of inheriting an autosomal dominant disease gene from this founder. Given an average inbreeding coefficient of 0.0016, the probability of inheriting two recessive disease genes from this founder is 0.000032. The incidence of autosomal dominant von Willebrand disease in Sottunga is greater than 10% while that of autosomal recessive tapetoretinal disease is 1.5%. We conclude, therefore, that the high frequencies of these diseases are not due to the disproportionate genetic contribution of one or a few particular founders. It is more likely that these disease genes occurred in high frequency in the initial population or were introduced repeatedly through time.
PubMed ID
3067585 View in PubMed
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Marital migration and genetic structure in Kitee, Finland.

https://arctichealth.org/en/permalink/ahliterature233740
Source
Ann Hum Biol. 1988 Jan-Feb;15(1):23-33
Publication Type
Article
Author
K. Pitkänen
L B Jorde
J H Mielke
J O Fellman
A W Eriksson
Author Affiliation
Department of Economic and Social History, University of Helsinki.
Source
Ann Hum Biol. 1988 Jan-Feb;15(1):23-33
Language
English
Publication Type
Article
Keywords
Emigration and Immigration
Finland
Genetics, Population
Geography
Humans
Marriage
Abstract
A genetic analysis of marital migration in Kitee, Finland, is presented. The data are based on 9970 marriages which took place between 1750 and 1877. The results of this analysis are compared with those of previous studies of the population of the Aland Islands, Finland. Analysis of inter-subdivision genetic kinship matrices shows that genetic heterogeneity in Kitee is substantially less than in Aland. This is due primarily to higher rates of migration, both between subdivisions and from outside the population, in Kitee compared to Aland. These differences in migration rates can in turn be attributed to greater geographic isolation in Aland and the contrasting social structures of the two populations. Because of differences in geographic structure and population distribution, geographic distance between subdivisions is a better predictor of inter-subdivision genetic kinship in Kitee than in Aland. The Aland Islands are known to have high frequencies of several otherwise rare genetic diseases; in addition, these diseases are distributed very non-randomly among Aland's subdivisions. The genetic structure results presented here suggest that Kitee should have a less unique distribution of genetic diseases.
PubMed ID
3348589 View in PubMed
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A mathematical model for recurrent twinning.

https://arctichealth.org/en/permalink/ahliterature103904
Source
Acta Genet Med Gemellol (Roma). 1990;39(3):307-16
Publication Type
Article
Date
1990
Author
J O Fellman
A W Eriksson
Author Affiliation
Folkhälsan Institute of Genetics, Population Genetics Unit, Helsinki, Finland.
Source
Acta Genet Med Gemellol (Roma). 1990;39(3):307-16
Date
1990
Language
English
Publication Type
Article
Keywords
Female
Humans
Infant, Newborn
Likelihood Functions
Models, Statistical
Pregnancy
Pregnancy, Multiple
Twins - statistics & numerical data
Abstract
In an attempt to improve our understanding of the factors that affect human twinning, we further developed the models given by Hellin (1895) and Peller (1946). The connection between these models and our own model ("Fellman's law") were studied. These attempts have resulted in a more general model, which was then applied to data from Aland Islands (1750-1939), Nmes (1790-1875), Stuttgart (about 1790-1900) and Utah (1850-1900). The product of the mean sibship size and the total twinning rate can be considered as a crude estimate of the expected number of sets of twins in a sibship. The same can be said about the twinning parameter in our model. These estimates are in good agreement. If we consider twinning data only, we obtain the geometric distribution, and log (Nk), where Nk is the number of mothers with k twin maternities, is a linear function of the number of recurrences. Graphically, this property can easily be checked. For sibships containing three or more sets of twins, all four populations show higher values than expected, particularly the populations from Stuttgart and Utah, which data also show poor agreement according to a chi 2-test. A more exact model would demand more detailed demographic information, such as distribution of sibship sizes, age-specific twinning rates and temporal variations in twinning. The observed number of mothers in Aland with several recurrences of multiple maternities shows a considerable excess over the expected number as predicted by Peller's rule. The parameters in our model can be estimated by the maximum likelihood method and the obtained model fits the data better then Peller's model.
PubMed ID
2085066 View in PubMed
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Population studies on the Aland Islands. I. Prediction of kinship from migration and isolation by distance.

https://arctichealth.org/en/permalink/ahliterature254968
Source
Hum Hered. 1973;23(5):422-33
Publication Type
Article
Date
1973

Secular changes of twinning rates in Nordic populations.

https://arctichealth.org/en/permalink/ahliterature64631
Source
Acta Genet Med Gemellol (Roma). 1995;44(3-4):141-62
Publication Type
Article
Date
1995
Author
A W Eriksson
C. Abbott
P J Kostense
J O Fellman
Author Affiliation
Institute of Genetics, Population Genetics Unit, Helsingfors, Finland.
Source
Acta Genet Med Gemellol (Roma). 1995;44(3-4):141-62
Date
1995
Language
English
Publication Type
Article
Keywords
Adult
Birth rate
Demography
Female
Finland
Humans
Male
Marital status
Maternal Age
Middle Aged
Parity
Pregnancy
Research Support, Non-U.S. Gov't
Scandinavia
Twins
PubMed ID
8739726 View in PubMed
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Statistical models for the twinning rate.

https://arctichealth.org/en/permalink/ahliterature65508
Source
Acta Genet Med Gemellol (Roma). 1987;36(3):297-312
Publication Type
Article
Date
1987
Author
J O Fellman
A W Eriksson
Author Affiliation
Folkhälsan Institute of Genetics, Population Genetics Unit, Helsinki, Finland.
Source
Acta Genet Med Gemellol (Roma). 1987;36(3):297-312
Date
1987
Language
English
Publication Type
Article
Keywords
Australia
Birth rate
Comparative Study
Denmark
Female
Finland
Humans
Italy
Marriage
Maternal Age
Models, Biological
Parity
Regression Analysis
Twins
Abstract
Linear regression models are used to explain the variations in the twinning rates. Data sets from different countries are analysed and maternal age, parity and marital status are the main regressors. The model building technique is also used in order to study the secular decline in the twinning rate. Linear regression technique makes it possible to compare the effect of different factors but the method requires sufficiently disaggregated data.
PubMed ID
3451642 View in PubMed
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Twinning rate in Scandinavia, Germany and The Netherlands during years of privation.

https://arctichealth.org/en/permalink/ahliterature234125
Source
Acta Genet Med Gemellol (Roma). 1988;37(3-4):277-97
Publication Type
Article
Date
1988
Author
A W Eriksson
W M Bressers
P J Kostense
K J Pitkänen
J H Mielke
L B Jorde
R F Tas
J O Fellman
Author Affiliation
Institute of Human Genetics, Medical Faculty, Free University, Amsterdam, The Netherlands.
Source
Acta Genet Med Gemellol (Roma). 1988;37(3-4):277-97
Date
1988
Language
English
Publication Type
Article
Keywords
Female
Fertility
Food Deprivation
Germany
Humans
Longitudinal Studies
Netherlands
Pregnancy
Pregnancy, Multiple
Scandinavia
Socioeconomic Factors
Abstract
Twinning rates were studied in Swedes, Aland Islanders, Finns, Germans, and Dutch during years of starvation when death rates were two to three times higher than average. In contrast to the situation among some animals, this study suggests that nutrition above a certain threshold is unimportant for human reproduction, including twinning. The twinning rates for these different populations display marked temporal differences, but low values in the twinning rate are not consistently associated with periods of epidemics, famine, or similar nutritional stress. After years of privation and/or separation of spouses, a rapid "catch-up effect" can often be seen in the twinning rates, as well as marriage and birth rates. Psychoendocrine factors and interparental immunological conditions that may be involved in this phenomenon are discussed.
PubMed ID
3075834 View in PubMed
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9 records – page 1 of 1.