Combining the meiotic drive gene D and the translocation T1 in the mosquito, Aedes Aegypti (L.). I. Sex-ratio distortion and fertility

AbstractReciprocal crosses between strains of Aedes aegypti (Linnaeus) from different geographical areas have revealed an unexpectedly complex pattern of holandrically inherited male biased sex ratios in F2. The variation has been interpreted in terms of a web of X–Y interactions in Fl, in which the Y chromosome may or may not show meiotic drive against the X chromosome with which it is paired. The pattern of inheritance is not in agreement with a single form of Y chromosome, driving with different degrees of intensity against Xs of different sensitivity, but indicates different forms of driving Y chromosome. A rule has emerged that if Fl males from any cross give rise to a male distorted sex ratio in their progeny (F2), the males from the reciprocal cross give rise to a normal sex ratio. All eleven newly colonized strains from Ghana showed Y meiotic drive against the Xs of five strains, one of American and four of Australian origin, although one of the eleven showed a greater degree of drive than the other ten against the same sensitive strains. The variation observed is discussed in relation to previous studies on meiotic drive by the MD haplotype, and to the possible exploitation of sex ratio distortion in controlling this potentially dangerous insect.

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Resistance to meiotic drive at the MD locus in an Indian wild population of Aedes aegypti

Genetics Research ◽

10.1017/s0016672300017195 ◽

1977 ◽

Vol 29 (2) ◽

pp. 123-132 ◽

Cited By ~ 18

Author(s):

S. G. Suguna ◽

R. J. Wood ◽

C. F. Curtis ◽

A. Whitelaw ◽

S. J. Kazmi

Keyword(s):

Sex Ratio ◽

Aedes Aegypti ◽

Genetic Control ◽

Wild Population ◽

Sex Ratios ◽

Meiotic Drive ◽

In The Wild ◽

Ratio Distortion ◽

Sex Ratio Distortion ◽

Different Parts

SUMMARYFemales from an Indian wild population of Aedes aegypti were crossed to males carrying the sex ratio distorter factor MD which shows meiotic drive. Progenies from F1 males were tested for sex ratio distortion, i.e. the chromosomes from the wild females were screened for their resistance to the action of MD. The distribution of sex ratio in the progenies of different F1 males indicated a polymorphism in the wild population for resistant and sensitive variants of the X chromosome. Seven discrete categories of X appear to exist, associated with sex ratios ranging from 50% ♀ to less than 1·25% ♀. The overall level of resistance varied slightly but significantly in different parts of a town. The results are discussed in relation to the use of sex ratio distortion for genetic control of mosquitoes.

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Sex Chromosome Meiotic Drive in Stalk-Eyed Flies

Genetics ◽

10.1093/genetics/147.3.1169 ◽

1997 ◽

Vol 147 (3) ◽

pp. 1169-1180 ◽

Cited By ~ 6

Author(s):

Daven C Presgraves ◽

Emily Severance ◽

Gerald S Willrinson

Keyword(s):

Sex Ratio ◽

Sex Chromosome ◽

Sex Ratios ◽

Natural Populations ◽

Meiotic Drive ◽

Operational Sex Ratio ◽

Genetic Modifiers ◽

Ratio Distortion ◽

The Impact ◽

Sex Ratio Distortion

Meiotically driven sex chromosomes can quickly spread to fixation and cause population extinction unless balanced by selection or suppressed by genetic modifiers. We report results of genetic analyses that demonstrate that extreme female-biased sex ratios in two sister species of stalk-eyed flies, Cyrtodiopsis dalmanni and C. whitei, are due to a meiotic drive element on the X chromosome (Xd). Relatively high frequencies of Xd in C. dalmanni and C. whitei (13–17% and 29%, respectively) cause female-biased sex ratios in natural populations of both species. Sex ratio distortion is associated with spermatid degeneration in male carriers of Xd. Variation in sex ratios is caused by Y-linked and autosomal factors that decrease the intensity of meiotic drive. Y-linked polymorphism for resistance to drive exists in C. dalmanni in which a resistant Y chromosome reduces the intensity and reverses the direction of meiotic drive. When paired with Xd, modifying Y chromosomes (Ym) cause the transmission of predominantly Y-bearing sperm, and on average, production of 63% male progeny. The absence of sex ratio distortion in closely related monomorphic outgroup species suggests that this meiotic drive system may predate the origin of C. whitei and C. dalmanni. We discuss factors likely to be involved in the persistence of these sex-linked polymorphisms and consider the impact of Xd on the operational sex ratio and the intensity of sexual selection in these extremely sexually dimorphic flies.

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Inheritance of Larval Resistance to Permethrin in Aedes aegypti and Association with Sex Ratio Distortion and Life History Variation

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.1997.56.456 ◽

1997 ◽

Vol 56 (4) ◽

pp. 456-465 ◽

Cited By ~ 27

Author(s):

Yemane B. Mebrahtu ◽

Martin Taylor ◽

John Norem

Keyword(s):

Life History ◽

Sex Ratio ◽

Aedes Aegypti ◽

Life History Variation ◽

Ratio Distortion ◽

Sex Ratio Distortion

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SEX RATIO DISTORTION CAUSED BY MEIOTIC DRIVE IN A MOSQUITO, Culex pipiens L

Genetics ◽

10.1093/genetics/88.3.427 ◽

1978 ◽

Vol 88 (3) ◽

pp. 427-446

Author(s):

Theresa Luine Sweeny ◽

A Ralph Barr

Keyword(s):

Sex Ratio ◽

Chromosome Pair ◽

Culex Pipiens ◽

Recessive Gene ◽

Meiotic Drive ◽

Female Offspring ◽

Large Excess ◽

Daughter Cells ◽

Ratio Distortion ◽

Sex Ratio Distortion

ABSTRACT A genetic factor, distorter (d), has been discovered that upsets the normal sex ratio of 1:1 and results in a large excess of males in Culex pipiens. The effect can be explained by a sex-linked, recessive gene. Males homozygous for the gene (Md/md) produce few female offspring; the effect is not due to postzygotic mortality. During the first meiotic division in spermatogenesis, the shortest chromosome pair, which, according to Jost and Laven (1971), is associated with sex determination, can be seen to be abnormal. In a high proportion of spermatocysts, one of the dyads of the shortest bivalent fragments, and the pieces are distributed irregularly to the daughter cells. It is believed that the female-determining chromosomes fragment. This would give rise to an excess of male-determining sperm. The possible usefulness of this factor for control or for experimental purposes is discussed.

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