ABSTRACT
BACKGROUND: In order to understand how selection is operating in the Gowda population, the index of opportunity for selection was calculated and the present findings were compared with some related findings from other South Indian (SI) populations. MATERIALS AND METHODS: Crow (1958) and the modified method by Johnston and Kensinger (1971) were used for the present purpose. RESULTS AND DISCUSSION: The index of total selection intensity (I) was found to be moderate taking into consideration the range for many Indian populations. Considering certain differences in fertility and mortality heritable, it appears that natural selection play an important role in shaping the genetic constitution of the Gowda population. Analysis of data indicates that the index due to fertility seems to contribute more towards selection than mortality. This trend might be because of better living condition and health-care system among the Gowdas which have a positive impact on the lower contribution of mortality for the evolution mechanism of the Gowda population through natural selection.
Subject(s)
Adult , Female , Humans , India , Infertility, Female/epidemiology , Infertility, Female/genetics , Infertility, Female/mortality , Population Groups/epidemiology , Population Groups/genetics , Rural Health , Selection, Genetic/geneticsABSTRACT
BACKGROUND: Selection potential based on differential fertility and mortality has been computed for seven population groups inhabiting different geographical locations of Northeast India. MATERIALS AND METHODS: Crow’s as well as Johnston and Kensinger’s index have been used for the present purpose. RESULTS AND CONCLUSION: Irrespective of the methodology, the total index of selection was found to be highest among the Deoris followed by the Kaibartas. The lowest selection index was found among the Oraon population. If the relative contribution of fertility and mortality components to the total index is considered to be multiplicative, it is observed that in all these communities the fertility component exceeds that of mortality component, which may indicate initiation of demographic transitional phase in the selected populations with the betterment of healthcare and socioeconomic condition within the last few decades.
Subject(s)
Demography/trends , Ethnicity/genetics , Female , Fertility/genetics , Humans , India , Mortality , Population Dynamics/trends , Population Groups/genetics , Selection, Genetic/genetics , WomenABSTRACT
Effects of inbreeding have been studied on diverse traits namely mortality, selection intensity and anthropometric traits in socio-economically divergent castes with different inbreeding levels taking into consideration the extent of marital migration and assortative marriage by profession in these populations. Mala, Madiga of the scheduled castes and Reddy, Vvsya and Maheshwari of the forward castes constituted the sample populations. Analysis of inbreeding effects revealed low mortality load, high selection intensity and inbreeding elevation of anthropometric traits in the forward castes. Wide differences in parameters of populations structure such as inbreeding, marital migration, assortative marriage by profession and gene-environment interactions could be causing differences in homozygosities of deleterious/ ill adapted genes in these castes leading to the results observed.