Estimating Intergenerational and Assortative Processes in Extended Family Data

Abstract

We quantify intergenerational and assortative processes by comparing different degrees of kinship within the same generation. This “horizontal” approach yields more, and more distant kinship moments than traditional methods, which allows us to account for the transmission of latent advantages in a detailed intergenerational model. Using Swedish registers, we find strong persistence in the latent determinants of status, and a striking degree of sorting – to explain the similarity of distant kins, assortative matching must be much stronger than previously thought. Latent genetic influences explain little of the variance in educational attainment, and sorting occurs primarily in non-genetic factors.

Non-random Mating Patterns in Education, Mental, and Somatic Health: A Population Study on Within- and Cross-Trait Associations

“…Roughly half of the variance in EA was not shared with GPA, indicating that there are important differences between the two. The current study indicates, as do also previous studies 19,24 , that the strong partner resemblance in EA is due to even stronger resemblance in an unobserved factor. This was also the case for GPA.…”

Confounding Fuels Misinterpretation in Human Genetics

“…The suggestion in (Clark, 2023a) that social inequality emanates from near-deterministic genetic inheritance of social status are at odds with recent literature (Akimova et al, 2023;Collado et al, 2023;Domingue et al, 2014;Yengo et al, 2018) . While estimates of narrow-sense heritability and the degree of assortative mating greatly depend on the population considered (geographically, genetically, socially and otherwise), definition of the trait, time, study characteristics and more, we discuss below some recent estimates of these parameters in genetic studies to contextualize estimates in (Clark, 2023a) .…”

“…Scholars from various disciplines have long appreciated the myriad ways in which phenotypic similarities among family members arise through non-genetic pathways ( Fig. 1 ) and may follow the same correlation patterns expected from genetic transmission (Barton et al, 2019;Cavalli-Sforza and Feldman, 1978, 1973a, 1973bCloninger et al, 1979aCloninger et al, , 1979bCollado et al, 2023;Feldman et al, 2013;Herzig et al, 2023;Lewontin et al, 1984;Rao et al, 1976Rao et al, , 1974Rice et al, 1980Rice et al, , 1978Solon, 2014;Uchiyama et al, 2022;Vilhjálmsson and Nordborg, 2013;Wright, 1931) . Mechanisms of non-genetic transmission include "ecological inheritance," where the trait value of an offspring is influenced by the environmental conditions created by their parents (e.g., familial wealth influencing educational opportunities) (Cavalli-Sforza and Feldman, 1978;Odling-Smee, 1988) , and the diffusion of information directly to one's relatives (e.g., literate parents teaching their children how to read) (Cavalli-Sforza and Feldman, 1973b) .…”

“…Non-genetic transmission is ubiquitous for social and behavioral traits and confounds estimation of the genetic sources of phenotypic resemblance between relatives [ cf. recent work describing such effects on educational attainment (Collado et al, 2023) and occupational status (Akimova et al, 2023) ].…”

“…For many of these non-genetic factors, transmission within families can parallel genetic transmission (Fig. 1) (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). When those attributes that are non-genetically transmitted contribute to variation among people, their relative contribution is indiscernible from that of genetics.…”